Curable composition, film, laminated body, and display apparatus

ABSTRACT

An object of the present invention is to provide a curable composition comprising a fluorescent particle containing a perovskite compound, wherein a decrease in the quantum yield of a film formed by curing the curable composition due to heat can be suppressed; a film formed by curing the curable composition; and a laminated body and a display apparatus comprising the film. Provided are a curable composition comprising a fluorescent particle (A) containing a perovskite compound, a photopolymerizable compound (B), a photopolymerization initiator (C), and an antioxidant (D); a film formed by curing the curable composition; and a laminated body and a display apparatus comprising the film.

TECHNICAL FIELD

The present invention relates to a curable composition, a film formed bycuring the curable composition, and a laminated body and a displayapparatus comprising the film.

BACKGROUND ART

In recent years, there has been a growing interest in perovskitecompounds having a high quantum yield as a wavelength conversionmaterial. For example, Patent Literature 1 discloses a light emittingcomponent that comprises a light emitting crystal having a perovskitestructure.

CITATION LIST Patent Literature

-   Patent Literature 1: Japanese Translation of PCT International    Application Publication No. 2018-506625

SUMMARY OF INVENTION Technical Problem

An object of the present invention is to provide a curable compositioncomprising a fluorescent particle containing a perovskite compound,wherein a decrease in the quantum yield of a film formed by curing thecurable composition due to heat can be suppressed; a film formed bycuring the curable composition; and a laminated body and a displayapparatus comprising the film.

Solution to Problem

The present invention provides the following curable composition, film,laminated body, and display apparatus.

[1] A curable composition comprising a fluorescent particle (A)containing a perovskite compound, a photopolymerizable compound (B), aphotopolymerization initiator (C), and an antioxidant (D).

[2] The curable composition according to [1], wherein the antioxidant(D) comprises at least one kind selected from the group consisting ofamine based antioxidants, sulfur based antioxidants, phenol basedantioxidants, and phosphorus based antioxidants.

[3] The curable composition according to [1] or [2], further comprisinga quantum dot (E).

[4] The curable composition according to any of [1] to [3], wherein theantioxidant (D) comprises a phenol based antioxidant.

[5] A film formed by curing the curable composition according to any of[1] to [4].

[6] A laminated body comprising the film according to [5] and a layerother than the film.

[7] A display apparatus comprising the film according to [5] or thelaminated body according to [6].

Advantageous Effects of Invention

A curable composition comprising a fluorescent particle containing aperovskite compound, wherein a decrease in the quantum yield of a filmformed by curing the curable composition due to heat can be suppressed;a film formed by curing the curable composition; and a laminated bodyand a display apparatus comprising the film, can be provided.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic cross-sectional view illustrating one example of alaminated body according to the present invention.

FIG. 2 is a schematic cross-sectional view illustrating one example of adisplay apparatus according to the present invention;

DESCRIPTION OF EMBODIMENTS

[Curable Composition]

A curable composition according to the present invention (hereinafter,also simply referred to as a “curable compound”) comprises a fluorescentparticle (A) containing a perovskite compound, a photopolymerizablecompound (B), a photopolymerization initiator (C), and an antioxidant(D). According to such a curable composition, a decrease in the quantumyield of a film formed by curing the curable composition due to heat canbe suppressed. That is, such a curable composition can exhibit a good QYmaintenance rate. The maintenance rate of the quantum yield of the filmdue to heat can be calculated as the percentage of the quantum yield “QY(after heat resistance test)” (%) of the cured film after the heatresistance test to the quantum yield “QY (after film formation” (%) ofthe cured film of the curable composition, and is represented by thefollowing expression as the QY maintenance rate A.QY maintenance rate A (%)=100×QY (after heat resistance test)/QY (afterfilm formation)

When the QY maintenance rate A is higher, a decrease in the quantumyield of the cured film due to heat tends to be smaller, which is thuspreferable. The QY maintenance rate A is preferably greater than 65%,more preferably 70% or more, and further preferably 80% or more. QY(after film formation) is preferably 40% or more, more preferably 50% ormore, further preferably 60% or more, even further preferably 65% ormore, and particularly preferably 80% or more.

Although the specific method for measuring QY (after heat resistancetest) and QY (after film formation) follows the description in[Examples], which will be mentioned below, for example, for a laminatedbody composed of a first PET film/the cured film of the curablecomposition/a second PET film, the quantum yield “QY (after filmformation)” (%) may be measured at an excitation light of 450 nm, atroom temperature, and under the atmosphere, using an absolute PL quantumyield spectrometer, and then, after performing a heat resistance test onthis laminated body, the quantum yield “QY (after heat resistance test)”(%) may be measured for the laminated body after the heat resistancetest in the same manner as described above. The heat resistance test canbe carried out by, for example, a method in which the laminated body isretained in the air at a temperature of 150° C. for 90 minutes, or thelike.

The curable composition according to the present invention has lightemitting properties. The term “light emitting properties” refers to anature of emitting light. The light emitting properties are preferably anature of emitting light upon excitation and more preferably a nature ofemitting light upon excitation by excitation light. The wavelength ofthe excitation light may be, for example, 200 nm or more and 800 nm orless, may be 250 nm or more and 750 nm or less, and may be 300 nm ormore and 700 nm or less.

The curable composition according to the present invention can be usedas, for example, a wavelength conversion material for displayapparatuses such as a light emitting diode (LED).

Note that the compounds exemplified in the present specification as eachcomponent that is included or may be included in the curable compositionmay be used alone or in combination with a plurality of kinds, unlessotherwise noted.

[1] Fluorescent Particle (A) Containing Perovskite Compound

A fluorescent particle (A) containing a perovskite compound[hereinafter, also simply referred to as a “fluorescent particle (A)”]is preferably a fluorescent particle composed of a perovskite compound.

The curable composition may comprise only one kind of fluorescentparticle (A) or may comprise two or more kinds thereof.

The perovskite compound is a compound having a perovskite type crystalstructure with A, B, and X as the components thereof.

A is a monovalent cation, which is a component positioned at each vertexof the hexahedron centered on B in the perovskite type crystalstructure.

X is at least one kind of ion selected from the group consisting ofhalide ions and a thiocyanate ion, representing a component positionedat each vertex of the octahedron centered on B in the perovskite typecrystal structure.

B is a metal ion, which is a component positioned at the center of thehexahedron having A at the vertices thereof and the octahedron having Xat the vertices thereof in the perovskite type crystal structure.

Although the particle diameter of the fluorescent particle (A) is notparticularly limited, from the viewpoint of maintaining a good crystalstructure, the diameter is preferably 1 nm or more, more preferably 2 nmor more, and further preferably 3 nm or more. From the viewpoint ofmaking it difficult for the fluorescent particle (A) to settle in thecurable composition, the particle diameter of the fluorescent particle(A) is preferably 10 μm or less, more preferably 1 μm or less, andfurther preferably 500 nm or less.

The upper limits and the lower limits described above can be arbitrarilycombined.

Although the particle diameter of the fluorescent particle (A) is notparticularly limited, from the viewpoint of making it difficult for thefluorescent particle (A) to settle in the curable composition and fromthe viewpoint of maintaining a good crystal structure, the diameter ispreferably 1 nm or more and 10 μm or less, more preferably 2 nm or moreand 1 μm or less, and further preferably 3 nm or more and 500 nm orless.

Although the particle size distribution of the fluorescent particle (A)is not particularly limited, from the viewpoint of maintaining a goodcrystal structure, the median diameter D50 is preferably 3 nm or more,more preferably 4 nm or more, and further preferably 5 nm or more. Fromthe viewpoint of making it difficult for the fluorescent particle (A) tosettle in the curable composition, the particle size distribution of thefluorescent particle (A) is preferably 5 μm or less, more preferably 500nm or less, and further preferably 100 nm or less.

The upper limits and the lower limits described above can be arbitrarilycombined.

The particle diameter and the particle size distribution of thefluorescent particle (A) can be determined by using a transmissionelectron microscope (TEM).

The perovskite compound with A, B, and X as the components thereof isnot particularly limited and may be a compound having any structure of athree dimensional structure, a two dimensional structure, or a quasi twodimensional structure.

In the case of the three dimensional structure, the perovskite compoundis represented by ABX_((3+δ)).

In the case of the two dimensional structure, the perovskite compound isrepresented by ABX_((4+δ)).

Here, δ is a number that can be changed as appropriate depending on thecharge balance of B, and is −0.7 or more and 0.7 or less.

The perovskite compound is preferably a perovskite compound representedby the following general formula (1).ABX _((3+δ))(−0.7≤δ≤0.7)  (1)[In the general formula (1), A represents a monovalent cation, Brepresents a metal ion, and X represents at least one kind of ionselected from the group consisting of halide ions and a thiocyanateion.]

In the perovskite compound, A is a monovalent cation, which is acomponent positioned at each vertex of the hexahedron centered on B inthe perovskite type crystal structure described above.

Examples of the monovalent cation include a cesium ion, an organicammonium ion, or an aminidium ion. When A is a cesium ion, an organicammonium ion having 3 or less carbon atoms, or an aminidium ion having 3or less carbon atoms in the perovskite compound, the perovskite compoundgenerally has a three dimensional structure represented by ABX_((3+δ)).

A in the perovskite compound is preferably a cesium ion or an organicammonium ion.

Specific examples of the organic ammonium ion of A include a cationrepresented by the following general formula (A1).

In the general formula (A1), R⁶ to R⁹ each independently represent ahydrogen atom, an alkyl group optionally having an amino group as thesubstituent, or a cycloalkyl group optionally having an amino group asthe substituent.

The alkyl group represented by R⁶ to R⁹ may be linear or branched, ormay have an amino group as the substituent.

The number of carbon atoms in the alkyl group represented by R⁶ to R⁹ isnormally 1 or more and 20 or less, preferably 1 or more and 4 or less,and more preferably 1 or more and 3 or less.

The cycloalkyl group represented by R⁶ to R⁹ may have an alkyl group oran amino group as the substituent.

The number of carbon atoms in the cycloalkyl group represented by R⁶ toR⁹ is normally 3 or more and 30 or less, preferably 3 or more and 11 orless, and more preferably 3 or more and 8 or less. The number of carbonatoms includes the number of carbon atoms in the substituent, as well.

It is preferable that the group represented by R⁶ to R⁹ should be eachindependently a hydrogen atom or an alkyl group.

By reducing the number of alkyl groups and cycloalkyl groups that can beincluded in the general formula (A1) and by reducing the number ofcarbon atoms in the alkyl groups and the cycloalkyl groups, a compoundhaving a three dimensional perovskite type crystal structure with a highquantum yield can be obtained.

When the number of carbon atoms in the alkyl groups or the cycloalkylgroups is 4 or more, a compound can be obtained that partially orentirely has a two dimensional and/or a quasi two dimensional (quasi-2D)perovskite type crystal structure. When the two dimensional perovskitetype crystal structure is infinitely laminated, it is equivalent to thethree dimensional perovskite type crystal structure (reference: P. P.Boix et al., J. Phys. Chem. Lett. 2015, 6, 898-907, and the like).

The total number of carbon atoms included in the alkyl groups and thecycloalkyl groups represented by R⁶ to R⁹ is preferably 1 or more and 4or less, and it is more preferable that one of R⁶ to R⁹ should be analkyl group having 1 or more and 3 or less carbon atoms and three of R⁶to R⁹ should be hydrogen atoms.

Examples of the alkyl group of R⁶ to R⁹ include a methyl group, an ethylgroup, a n-propyl group, an isopropyl group, a n-butyl group, anisobutyl group, a sec-butyl group, a tert-butyl group, a n-pentyl group,an isopentyl group, a neopentyl group, a tert-pentyl group, a1-methylbutyl group, a n-hexyl group, a 2-methylpentyl group, a3-methylpentyl group, a 2,2-dimethylbutyl group, a 2,3-dimethylbutylgroup, a n-heptyl group, a 2-methylhexyl group, a 3-methylhexyl group, a2,2-dimethylpentyl group, a 2,3-dimethylpentyl group, a2,4-dimethylpentyl group, a 3,3-dimethylpentyl group, a 3-ethylpentylgroup, a 2,2,3-trimethylbutyl group, a n-octyl group, an isooctyl group,a 2-ethylhexyl group, a nonyl group, a decyl group, an undecyl group, adodecyl group, a tridecyl group, a tetradecyl group, a pentadecyl group,a hexadecyl group, a heptadecyl group, an octadecyl group, a nonadecylgroup, and an icosyl group.

Examples of the cycloalkyl group of R⁶ to R⁹ include those in which thealkyl groups having 3 or more carbon atoms exemplified as the alkylgroup of R⁶ to R⁹ form a ring, and specific examples thereof include acyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclooctyl group, a cyclononyl group, acyclodecyl group, a norbornyl group, an isobornyl group, a 1-adamantylgroup, a 2-adamantyl group, a tricyclodecyl group, and the like.

The organic ammonium ion represented by A is preferably CH₃NH₃ ₊ (amethyl ammonium ion), C₂H₅NH₃ ₊ (an ethyl ammonium ion), or C₃H₇NH₃ ₊ (apropyl ammonium ion), more preferably CH₃NH₃ ₊ or C₂H₅NH₃ ₊ , andfurther preferably CH₃NH₃ ₊ .

Examples of the aminidium ion represented by A include, for example, anaminidium ion represented by the following general formula (A2).(R¹⁰R¹¹N═CH—NR¹²R¹³)⁺  (A2)

In the general formula (A2), R¹⁰ to R¹³ each independently represent ahydrogen atom, an alkyl group optionally having an amino group as thesubstituent, or a cycloalkyl group optionally having an amino group asthe substituent.

The alkyl group represented by R¹⁰ to R¹³ may be linear or branched, ormay have an amino group as the substituent.

The number of carbon atoms in the alkyl group represented by R¹⁰ to R¹³is normally 1 or more and 20 or less, preferably 1 or more and 4 orless, and more preferably 1 or more and 3 or less.

The cycloalkyl group represented by R¹⁰ to R¹³ may have an alkyl groupor an amino group as the substituent.

The number of carbon atoms in the cycloalkyl group represented by R¹⁰ toR¹³ is normally 3 or more and 30 or less, preferably 3 or more and 11 orless, and more preferably 3 or more and 8 or less. The number of carbonatoms includes the number of carbon atoms in the substituent.

Specific examples of the alkyl group of R¹⁰ to R¹³ include the alkylgroups exemplified for R⁶ to R⁹.

Specific examples of the cycloalkyl group of R¹⁰ to R¹³ include thecycloalkyl groups exemplified for R⁶ to R⁹.

It is preferable that the group represented by R¹⁰ to R¹³ should be ahydrogen atom or an alkyl group.

By reducing the number of alkyl groups and cycloalkyl groups that areincluded in the general formula (A2) and by reducing the number ofcarbon atoms in the alkyl groups and the cycloalkyl groups, a perovskitecompound having a three dimensional structure with a high quantum yieldcan be obtained.

When the number of carbon atoms in the alkyl groups or the cycloalkylgroups is 4 or more, a compound can be obtained that partially orentirely has a two dimensional and/or a quasi two dimensional (quasi-2D)perovskite type crystal structure.

The total number of carbon atoms included in the alkyl groups and thecycloalkyl groups represented by R¹⁰ to R¹³ is preferably 1 or more and4 or less, and it is more preferable that R¹⁰ should be an alkyl grouphaving 1 or more and 3 or less carbon atoms and R¹¹ to R¹³ should behydrogen atoms.

In the perovskite compound, B is a metal ion, which is a componentpositioned at the center of the hexahedron having A at the verticesthereof and the octahedron having X at the vertices thereof in theperovskite type crystal structure described above.

The metal ion of the component B may be an ion composed of one or morekinds selected from the group consisting of monovalent metal ions,divalent metal ions, and trivalent metal ions. It is preferable that Bshould include a divalent metal ion, and it is more preferable that itshould include one or more kinds of metal ions selected from the groupconsisting of lead and tin.

In the perovskite compound, X represents at least one kind of ionselected from the group consisting of halide ions and a thiocyanate ion,representing a component positioned at each vertex of the octahedroncentered on B in the perovskite type crystal structure described above.

X may be at least one kind of ion selected from the group consisting ofa chloride ion, a bromide ion, a fluoride ion, an iodide ion, and athiocyanate ion.

Although X can be selected as appropriate depending on a desiredemission wavelength, for example, X can include a bromide ion.

When X comprises two or more kinds of halide ions, the content ratio ofthose halide ions can be selected as appropriate depending on theemission wavelength, and for example, a combination of a bromide ion anda chloride ion or a combination of a bromide ion and an iodide ion canbe used.

Preferable examples of the perovskite compound represented byABX_((3+δ)), having a three dimensional perovskite type crystalstructure, specifically include

CH₃NH₃PbBr₃, CH₃NH₃PbCl₃, CH₃NH₃PbI₃, CH₃NH₃PbBr_((3−y))I_(y) (0<y<3),CH₃NH₃PbBr_((3−y))Cl_(y) (0<y<3), (H₂N═CH—NH₂)PbBr₃, (H₂N═CH—NH₂)PbCl₃,(H₂N═CH—NH₂)PbI₃,

CH₃NH₃Pb_((1-a))CaaBr₃ (0<a≤0.7), CH₃NH₃Pb_((1-a))Sr_(a)Br₃ (0<a≤0.7),CH₃NH₃Pb_((1-a))La_(a)Br_((3+δ)) (0<a≤0.7, 0<δ≤0.7),CH₃NH₃Pb_((1-a))Ba_(a)Br₃ (0<a≤0.7), CH₃NH₃Pb_((1-a))Dy_(a)Br_((3+δ))(0<a≤0.7, 0<δ≤0.7),

CH₃NH₃Pb_((1-a))Na_(a)Br_((3+δ)) (0<a≤0.7, −0.7≤δ<0),CH₃NH₃Pb_((1-a))Li_(a)Br_((3+δ)) (0<a≤0.7, −0.7≤δ<0),

CsPb_((1-a))Na_(a)Br_((3+δ)) (0<a≤0.7, −0.7δ<0),CsPb_((1-a))Li_(a)Br_((3+δ)) (0<a≤0.7, −0.7≤δ<0),

CH₃NH₃Pb_((1-a))Na_(a)Br_((3+δ-y))I_(y) (0<a≤0.7, −0.7≤δ<0, 0<y<3),CH₃NH₃Pb_((1-a))Li_(a)Br_((3+δ-y))I_(y) (0<a≤0.7, −0.7≤δ0, 0<y<3),CH₃NH₃Pb_((1-a))Na_(a)Br_((3+δ-y))Cl_(y) (0<a≤0.7, −0.7≤δ<0, 0<y<3),CH₃NH₃Pb_((1-a))Li_(a)Br_((3+δ-y))Cl_(y) (0<a≤0.7, −0.7≤δ<0, 0<y<3),

(H₂N═CH—NH₂)Pb_((1-a))Na_(a)Br_((3+δ)) (0<a≤0.7, −0.7≤δ<0),(H₂N═CH—NH₂)Pb_((1-a))Li_(a)Br_((3+δ)) (0<a≤0.7, −0.7≤δ<0),(H₂N═CH—NH₂)Pb_((1-a))Na_(a)Br_((3+δ-y))I_(y) (0<a≤0.7, −0.7≤δ<0,0<y<3), (H₂N═CH—NH₂)Pb_((1-a))Na_(a)Br_((3+δ-y))Cl_(y) (0<a≤0.7,−0.7≤δ<0, 0<y<3),

CsPbBr₃, CsPbCl₃, CsPbI₃, CsPbBr_((3−y))I_(y) (0<y<3),CsPbBr_((3−y))Cl_(y) (0<y<3), CH₃NH₃PbBr_((3−y))Cl_(y) (0<y<3),

CH₃NH₃Pb_((1-a))Zn_(a)Br₃ (0<a≤0.7), CH₃NH₃Pb_((1-a))Al_(a)Br_((3+δ))(0<a≤0.7, 0≤δ≤0.7), CH₃NH₃Pb_((1-a))Co_(a)Br₃ (0<a≤0.7),CH₃NH₃Pb_((1-a))Mn_(a)Br₃ (0<a≤0.7), CH₃NH₃Pb_((1-a))Mg_(a)Br₃(0<a≤0.7),

CsPb_((1-a))Zn_(a)Br₃ (0<a≤0.7), CsPb_((1-a))Al_(a)Br_((3+δ)) (0<a≤0.7,0<δ≤0.7), CsPb_((1-a))Co_(a)Br₃ (0<a≤0.7), CsPb_((1-a))Mn_(a)Br₃(0<a≤0.7), CsPb_((1-a))Mg_(a)Br₃ (0<a≤0.7),

CH₃NH₃Pb_((1-a))Zn_(a)Br_((3−y))I_(y) (0<a≤0.7, 0<y<3),CH₃NH₃Pb_((1-a))Al_(a)Br_((3+δ-y))I_(y) (0<a≤0.7, 0<δ≤0.7, 0<y<3),CH₃NH₃Pb_((1-a))Co_(a)Br_((3−y))I_(y) (0<a≤0.7, 0<y<3),CH₃NH₃Pb_((1-a))Mn_(a)Br_((3−y))I_(y) (0<a≤0.7, 0<y<3),CH₃NH₃Pb_((1-a))Mg_(a)Br_((3−y))I_(y) (0<a≤0.7, 0<y<3),CH₃NH₃Pb_((1-a))Zn_(a)Br_((3−y))Cl_(y) (0<a≤0.7, 0<y<3),CH₃NH₃Pb_((1-a))Al_(a)Br_((3+δ-y))Cl_(y) (0<a≤0.7, 0<δ0.7, 0<y<3),CH₃NH₃Pb_((1-a))CO_(a)Br_((3+δ-y))Cl_(y) (0<a≤0.7, 0<y<3),CH₃NH₃Pb_((1-a))Mn_(a)Br_((3−y))Cl_(y) (0<a≤0.7, 0<y<3),CH₃NH₃Pb_((1-a))Mg_(a)Br_((3−y))Cl_(y) (0<a≤0.7, 0<y<3),

(H₂N═CH—NH₂)Zn_(a)Br₃) (0<a≤0.7), (H₂N═CH—NH₂)Mg_(a)Br₃ (0<a≤0.7),(H₂N═CH—NH₂)Pb_((1-a))Zn_(a)Br_((3−y))I_(y) (0<a≤0.7, 0<y<3),(H₂N═CH—NH₂)Pb_((1-a))Zn_(a)Br_((3−y))Cl_(y) (0<a≤0.7, 0<y<3), and thelike.

Preferable examples of the perovskite compound represented byA₂BX_((4+δ)), having a two dimensional perovskite type crystalstructure, specifically include

(C₄H₉NH₃)₂PbBr₄, (C₄H₉NH₃)₂PbCl₄, (C₄H₉NH₃)₂PbI₄, (C₇H₁₅NH₃)₂PbBr₄,(C₇H₁₅NH₃)₂PbCl₄, (C₇H₁₅NH₃)₂PbI₄, (C₄H₉NH₃)₂Pb_((1-a))Li_(a)Br_((4+δ))(0<a≤0.7, −0.7≤δ<0), (C₄H₉NH₃)₂Pb_((1-a))Na_(a)Br_((4+δ)) (0<a≤0.7,−0.7≤δ<0), (C₄H₉NH₃)₂Pb_((1-a))Rb_(a)Br_((4+δ)) (0<a≤0.7, —0.7≤δ<0),

(C₇H₁₅NH₃)₂Pb_((1-a))Na_(a)Br_((4+δ)) (0<a≤0.7, —0.7≤δ<0),(C₇H₁₅NH₃)₂Pb_((1-a))Li_(a)Br_((4+δ)) (0<a≤0.7, —0.7≤δ<0),(C₇H₁₅NH₃)₂Pb_((1-a))Rb_(a)Br_((4+δ)) (0<a≤0.7, −0.7≤δ<0),

(C₄H₉NH₃)₂Pb_((1-a))Na_(a)Br_((4+δ-y))I_(y) (0<a≤0.7, −0.7≤δ<0, 0<y<4),(C₄H₉NH₃)₂Pb_((1-a))Li_(a)Br_((4+δ-y))I_(y) (0<a≤0.7, −0.7≤δ3<0, 0<y<4),(C₄H₉NH₃)₂Pb_((1-a))Rb_(a)Br_((4+δ-y))I_(y) (0<a≤0.7, −0.7≤δ<0, 0<y<4),

(C₄H₉NH₃)₂Pb_((1-a))Na_(a)Br_((4+δ-y))Cl_(y) (0<a≤0.7, −0.7≤δ<0, 0<y<4),(C₄H₉NH₃)₂Pb_((1-a))Li_(a)Br_((4+δ-y))Cl_(y) (0<a≤0.7, −0.7≤δ<0, 0<y<4),(C₄H₉NH₃)₂Pb_((1-a))Rb_(a)Br_((4+δ-y))Cl_(y) (0<a≤0.7, −0.7≤δ<0, 0<y<4),

(C₄H₉NH₃)₂PbBr₄, (C₇H₁₅NH₃)₂PbBr₄,

(C₄H₉NH₃)₂PbBr_((4−y))Cl_(y) (0<y<4), (C₄H₉NH₃)₂PbBr_((4−y))I_(y)(0<y<4),

(C₄H₉NH₃)₂Pb_((1-a))Zn_(a)Br₄ (0<a≤0.7), (C₄H₉NH₃)₂Pb_((1-a))Mg_(a)Br₄(0<a≤0.7), (C₄H₉NH₃)₂Pb_((1-a))Co_(a)Br₄ (0<a≤0.7),(C₄H₉NH₃)₂Pb_((1-a))Mn_(a)Br₄ (0<a≤0.7),

(C₇H₁₅NH₃)₂Pb_((1-a))Zn_(a)Br₄ (0<a≤0.7), (C₇H₁₅NH₃)₂Pb_((1-a))Mg_(a)Br₄(0<a≤0.7), (C₇H₁₅NH₃)₂Pb_((1-a))Co_(a)Br₄ (0<a≤0.7),(C₇H₁₅NH₃)₂Pb_((1-a))Mn_(a)Br₄ (0<a≤0.7),

(C₄H₉NH₃)₂Pb_((1-a))Zn_(a)Br_((4−y))I_(y) (0<a≤0.7, 0<y<4),(C₄H₉NH₃)₂Pb_((1-a))Mg_(a)Br_((4−y))I_(y) (0<a≤0.7, 0<y<4),(C₄H₉NH₃)₂Pb_((1-a))Co_(a)Br_((4−y))I_(y) (0<a≤0.7, 0<y<4),(C₄H₉NH₃)₂Pb_((1-a))Mn_(a)Br_((4−y))I_(y) (0<a≤0.7, 0<y<4),

(C₄H₉NH₃)₂Pb_((1-a))Zn_(a)Br_((4−y))Cl_(y) (0<a≤0.7, 0<y<4),(C₄H₉NH₃)₂Pb_((1-a))Mg_(a)Br_((4−y))Cl_(y) (0<a≤0.7, 0<y<4),(C₄H₉NH₃)₂Pb_((1-a))Co_(a)Br_((4−y))Cl_(y) (0<a≤0.7, 0<y<4),(C₄H₉NH₃)₂Pb_((1-a))Mn_(a)Br_((4−y))Cl_(y) (0<a≤0.7, 0<y<4), and thelike.

The perovskite compound is a light emitter that is capable of emittingfluorescence in the visible light wavelength region, and when X is abromide ion, it can emit fluorescence with a maximum peak of intensityin the wavelength range, normally at 480 nm or more, preferably at 500nm or more, and more preferably at 520 nm or more, and normally at 700nm or less, preferably at 600 nm or less, and more preferably at 580 nmor less.

The upper limits and the lower limits described above can be arbitrarilycombined.

When X is an iodide ion, the perovskite compound can emit fluorescencewith a maximum peak of intensity in the wavelength range, normally at520 nm or more, preferably at 530 nm or more, and more preferably at 540nm or more, and normally at 800 nm or less, preferably at 750 nm orless, and more preferably at 730 nm or less.

The upper limits and the lower limits described above can be arbitrarilycombined.

When X is a chloride ion, the perovskite compound can emit fluorescencewith a maximum peak of intensity in the wavelength range, normally at300 nm or more, preferably at 310 nm or more, and more preferably at 330nm or more, and normally at 600 nm or less, preferably at 580 nm orless, and more preferably at 550 nm or less.

The upper limits and the lower limits described above can be arbitrarilycombined.

The fluorescent particle (A) can be, for example, a red fluorescentparticle, a green fluorescent particle, or a blue fluorescent particle.Upon irradiation of light, the red fluorescent particle releases redlight, the green fluorescent particle releases green light, and the bluefluorescent particle releases blue light.

Although the content of the fluorescent particle (A) in the curablecomposition is not particularly limited, from the viewpoint of making itdifficult for the fluorescent particle (A) to be condensed and from theviewpoint of preventing concentration quenching, it is preferably 50% bymass or less in 100% by mass of the curable composition, more preferably5% by mass or less, and further preferably 1% by mass or less. Inaddition, from the viewpoint of obtaining a good emission intensity, thecontent is preferably 0.0001% by mass or more, more preferably 0.001% bymass or more, and further preferably 0.01% by mass or more.

The upper limits and the lower limits described above can be arbitrarilycombined.

The content of the fluorescent particle (A) in the curable compositionis normally 0.0001% by mass or more and 50% by mass or less in 100% bymass of the curable composition.

The content of the fluorescent particle (A) in the curable compositionis preferably 0.0001% by mass or more and 5% by mass or less in 100% bymass of the curable composition, and is more preferably 0.0005% by massor more and 2% by mass or less.

A composition in which the content of the fluorescent particle (A) iswithin the range described above is preferable in that the aggregationof the fluorescent particle (A) is less likely to occur and the lightemitting properties are also demonstrated well.

[2] Photopolymerizable Compound (B)

A photopolymerizable compound (B) is a curable component contained inthe curable composition.

The photopolymerizable compound refers to a compound having apolymerizable unsaturated group that can be polymerized by irradiatingwith light such as ultraviolet light and visible light.

The curable composition may comprise only one kind of photopolymerizablecompound (B) or may comprise two or more kinds thereof.

Although the photopolymerizable compound (B) is not particularly limitedas long as it is a compound having one or more polymerizable unsaturatedgroups, from the viewpoint of enhancing the optical characteristics ofthe cured film, it preferably includes a (meth)acrylic compound.

The term (meth)acrylic compound means a compound having one or more ofat least one kind selected from the group consisting of a methacryloylgroup and an acryloyl group in the molecule.

In the same manner, (meth)acryloyl means at least one kind selected fromthe group consisting of methacryloyl and acryloyl.

(Meth)acryloyloxy means at least one kind selected from the groupconsisting of methacryloyloxy and acryloyloxy.

(Meth)acrylate means at least one kind selected from the groupconsisting of methacrylate and acrylate.

From the viewpoint of enhancing the optical characteristics of the curedfilm, the greater the content of the (meth)acrylic compound in thephotopolymerizable compound (B), the more preferable it is. Such acontent is more preferably 50% by mass or more in 100% by mass of thephotopolymerizable compound (B), and further preferably 70% by mass ormore. The photopolymerizable compound (B) may be composed solely of a(meth)acrylic compound.

From the viewpoint of enhancing the curability of the curablecomposition, it is preferable that the (meth)acrylic compound should bean acrylic compound among acrylic compounds and methacrylic compounds.It is more preferable that the photopolymerizable compound (B) should becomposed solely of an acrylic compound.

The acrylic compound means a compound having one or more acryloyl groupsin the molecule and not having a methacryloyl group.

The methacrylic compound means a compound having one or moremethacryloyl groups in the molecule and not having an acryloyl group.

The acrylic compound is preferably an acrylate compound.

The acrylate compound means a compound having one or more acryloyloxygroups in the molecule and not having a methacryloyloxy group. Onetypical example of the acrylate compound is an acrylic acid ester.

Examples of the (meth)acrylic compound having one (meth)acryloyloxygroup in the molecule as the polymerizable unsaturated group describedabove include methyl (meth)acrylate, ethyl (meth)acrylate, methoxyethyl(meth)acrylate, ethoxyethyl (meth)acrylate, n-propyl (meth)acrylate,isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl(meth)acrylate, tert-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate,cyclohexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate,nonyl (meth)acrylate, dodecyl (meth)acrylate, lauryl (meth)acrylate,stearyl (meth)acrylate, cyclopentyl (meth)acrylate, cyclohexyl(meth)acrylate, 2-methylcyclohexyl (meth)acrylate, isobornyl(meth)acrylate, adamantyl (meth)acrylate, allyl (meth)acrylate,propargyl (meth)acrylate, phenyl (meth)acrylate, naphthyl(meth)acrylate, benzyl (meth)acrylate, nonylphenylcarbitol(meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate,2-ethylhexylcarbitol (meth)acrylate, and the like.

Examples of the (meth)acrylic compound having two (meth)acryloyloxygroups in the molecule as the polymerizable unsaturated group describedabove include ethylene glycol di(meth)acrylate, triethylene glycoldi(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,6-hexanedioldi(meth)acrylate, 1,7-heptanediol di(meth)acrylate, 1,8-ocatanedioldi(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1,10-decanedioldi(meth)acrylate, 3-ethylpentanediol di(meth)acrylate, and the like.

Examples of the (meth)acrylic compound having three or more(meth)acryloyloxy groups in the molecule as the polymerizableunsaturated group described above include trimethylolpropanetri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritoltetra(meth)acrylate, dipentaerythritol penta(meth)acrylate,dipentaerythritol hexa(meth)acrylate, tripentaerythritolocta(meth)acrylate, tripentaerythritol hepta(meth)acrylate,tetrapentaerythritol deca(meth)acrylate, tetrapentaerythritolnona(meth)acrylate, ethylene glycol modified trimethylolpropanetri(meth)acrylate, propylene glycol modified trimethylolpropanetri(meth)acrylate, ethylene glycol modified pentaerythritoltetra(meth)acrylate, propylene glycol modified pentaerythritoltetra(meth)acrylate, ethylene glycol modified dipentaerythritolhexa(meth)acrylate, propylene glycol modified dipentaerythritolhexa(meth)acrylate, caprolactone modified pentaerythritoltetra(meth)acrylate, caprolactone modified dipentaerythritolhexa(meth)acrylate, and the like.

From the viewpoint of enhancing the hardness of the cured film, the(meth)acrylic compound preferably comprises a (meth)acrylic compoundhaving one (meth)acryloyl group and/or (meth)acrylic compound having two(meth)acryloyl groups in the molecule and a (meth)acrylic compoundhaving three or more (meth)acryloyl groups in the molecule, morepreferably comprises a (meth)acrylic compound having one(meth)acryloyloxy group and/or (meth)acrylic compound having two(meth)acryloyloxy groups in the molecule and a (meth)acrylic compoundhaving three or more (meth)acryloyloxy groups in the molecule, andfurther preferably comprises a (meth)acrylic compound having oneacryloyloxy group and/or acrylic compound having two acryloyloxy groupsin the molecule and an acrylic compound having three or more acryloyloxygroups in the molecule.

Although the content of the photopolymerizable compound (B) in thecurable composition is not particularly limited, it is, for example, 5%by mass or more and 99% by mass or less in 100% by mass of the solidcontent of the curable composition, preferably 10% by mass or more and99% by mass or less, more preferably 20% by mass or more and 99% by massor less, further preferably 40% by mass or more and 99% by mass or less,and even further preferably 50% by mass or more and 99% by mass or less.

When the content of the photopolymerizable compound (B) is within therange described above, there is a tendency that the mechanicalcharacteristics and optical characteristics of the cured film of thecurable composition are good.

The solid content of the curable composition shall refer to the total ofall components contained in the curable composition, excluding thesolvent.

[3] Photopolymerization Initiator (C)

A photopolymerization initiator (C) is not particularly limited as longas it is a compound that generates active radicals, acids, and the likeunder the action of light and can initiate the polymerization of thephotopolymerizable compound (B).

The curable composition may comprise only one kind ofphotopolymerization initiator (C) or may comprise two or more kindsthereof.

Although the photopolymerization initiator (C) is not particularlylimited, examples thereof include oxime based compounds such asO-acyloxime compounds, alkylphenone compounds, acylphosphine oxidecompounds, and the like. Preferable examples of the photopolymerizationinitiator include oxime based compounds such as O-acyloxime compounds.

The O-acyloxime compound is a compound having the structure representedby the following formula (d). Hereinafter, * represents a bonding hand.

Examples of the O-acyloxime compound includeN-benzoyloxy-1-(4-phenylsulfanylphenyl)butan-1-one-2-imine,N-benzoyloxy-1-(4-phenylsulfanylphenyl)octan-1-one-2-imine,N-benzoyloxy-1-(4-phenylsulfanylphenyl)-3-cyclopentylpropan-1-one-2-imine,N-acetoxy-1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethane-1-imine,N-acetoxy-1-[9-ethyl-6-{2-methyl-4-(3,3-dimethyl-2,4-dioxacyclopentanylmethyloxy)benzoyl}-9H-carbazol-3-yl]ethane-1-imine,N-acetoxy-1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-3-cyclopentylpropane-1-imine,N-benzoyloxy-1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-3-cyclopentylpropan-1-one-2-imine,N-acetyloxy-1-[4-(2-hydroxyethyloxy)phenylsulfanylphenyl]propan-1-one-2-imine,N-acetyloxy-1-[4-(1-methyl-2-methoxyethoxy)-2-methylphenyl]-1-(9-ethyl-6-nitro-9H-carbazol-3-yl)methan-1-imine,and the like.

Commercial products such as IRGACURE (trade name) OXE01, OXE02, andOXE03 (all manufactured by BASF SE), and N-1919, NCI-930, and NCI-831(all manufactured by ADEKA CORPORATION) may be used as well.

The alkylphenone compound is a compound having a substructurerepresented by the following formula (d4) or a substructure representedby the following formula (d5). In these substructures, the benzene ringoptionally has a substituent.

Examples of the compound having a structure represented by the formula(d4) include2-methyl-2-morpholino-1-(4-methylsulfanylphenyl)propan-1-one,2-dimethylamino-1-(4-morpholinophenyl)-2-benzylbutan-1-one,2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]butan-1-one,and the like.

Commercial products such as Omnirad (trade name) 369, 907, and 379 (allmanufactured by IGM Resins B.V.) may be used as well.

Examples of the compound having a structure represented by the formula(d5) include 2-hydroxy-2-methyl-1-phenylpropan-1-one,2-hydroxy-2-methyl-1-[4-(2-hydroxyethoxy)phenyl]propan-1-one,1-hydroxycyclohexyl phenyl ketone, an oligomer of2-hydroxy-2-methyl-1-(4-isopropenylphenyl)propan-1-one,α,α-diethoxyacetophenone, benzyl dimethyl ketal, and the like.

Examples of the acylphosphine oxide compound includephenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (for example, tradename “omnirad 819” (manufactured by IGM Resins B.V.)),2,4,6-trimethylbenzoyldiphenylphosphine oxide, and the like. Sinceacylphosphine oxide compounds have a photobleaching effect, they can bepreferably used in order to obtain a cured film with a thickness of 10μm or more.

Further examples of the photopolymerization initiator (C) include:

benzoin compounds such as benzoin, benzoin methyl ether, benzoin ethylether, benzoin isopropyl ether, and benzoin isobutyl ether;

benzophenone compounds such as benzophenone, methyl o-benzoylbenzoate,4-phenylbenzophenone, 4-benzoyl 4′-methyldiphenyl sulfide,3,3′,4,4′-tetra(tert-butylperoxycarbonyl)benzophenone,2,4,6-trimethylbenzophenone, and4,4′-di(N,N′-dimethylamino)-benzophenone;

xanthone compounds such as 2-isopropylthioxanthone and2,4-diethylthioxanthone;

anthracene compounds such as 9,10-dimethoxyanthracene,2-ethyl-9,10-dimethoxyanthracene, 9,10-diethoxyanthracene, and2-ethyl-9,10-diethoxyanthracene;

quinone compounds such as 9,10-phenanthrenequinone,2-ethylanthraquinone, and camphorquinone;

benzil, methyl phenylglyoxylate, titanocene compounds;

and the like.

In addition, examples of the photopolymerization initiator having arelatively low absorbance for light at a wavelength of 365 nm include,for example, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one,4-methoxy-3,3′-dimethylbenzophenone,2,2-dimethoxy-1,2-diphenylethan-1-one, 1-hydroxy-cyclohexyl phenylketone,1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one,2-hydroxy-1-1{4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]-phenyl}-2-methyl-propan-1-one,trimethylolpropane tris(3-mercaptopropionate),2-dimethylamino-2-(4-methyl-benzyl)-1-(4-morpholin-4-yl-phenyl)-butan-1-one,and compounds represented by the following formulas, and the like.

Although the content of the photopolymerization initiator (C) in thecurable composition is not particularly limited, it is, for example,0.02% by mass or more and 20% by mass or less in 100% by mass of thesolid content of the curable composition, preferably 0.05% by mass ormore and 10% by mass or less, more preferably 0.1% by mass or more and5% by mass or less, further preferably 0.2% by mass or more and 5% bymass or less, and even further preferably 0.3% by mass or more and 5% bymass or less.

When the content of the photopolymerization initiator (C) is within therange described above, there is a tendency that both curability andoptical characteristics can be achieved.

[4] Antioxidant (D)

The curable composition comprises an antioxidant (D). As a result ofthis, a decrease in the quantum yield of a film formed by curing thecurable composition due to heat can be suppressed.

The curable composition may comprise only one kind of antioxidant (D) ormay comprise two or more kinds thereof.

Examples of the antioxidant (D) include, for example, amine basedantioxidants, sulfur based antioxidants, phenol based antioxidants,phosphorus based antioxidants, metal compound based antioxidants, andthe like. From the viewpoint of more effectively suppressing thedecrease in the quantum yield due to heat described above, theantioxidant (D) preferably comprises at least one kind selected from thegroup consisting of amine based antioxidants, sulfur based antioxidants,phenol based antioxidants, and phosphorus based antioxidants, and morepreferably comprises at least one kind selected from the groupconsisting of sulfur based antioxidants, phenol based antioxidants, andphosphorus based antioxidants.

The amine based antioxidant is an antioxidant having an amino group inthe molecule.

Examples of the amine based antioxidant include, for example,naphthylamine based antioxidants such as 1-naphthylamine,phenyl-1-naphthylamine, p-octylphenyl-1-naphthylamine,p-nonylphenyl-1-naphthylamine, p-dodecylphenyl-1-naphthylamine, andphenyl-2-naphthylamine; phenylenediamine based antioxidants such asN,N′-diisopropyl-p-phenylenediamine, N,N′-diisobutyl-p-phenylenediamine,N,N′-diphenyl-p-phenylenediamine, N,N′-di-β-naphthyl-p-phenylenediamine,N-phenyl-N′-isopropyl-p-phenylenediamine,N-cyclohexyl-N′-phenyl-p-phenylenediamine,N-1,3-dimethylbutyl-N′-phenyl-p-phenylenediamine,dioctyl-p-phenylenediamine, phenylhexyl-p-phenylenediamine, andphenyloctyl-p-phenylenediamine; diphenylamine based antioxidants such asdipyridylamine, diphenylamine, p,p′-di-n-butyldiphenylamine,p,p′-di-tert-butyldiphenylamine, p,p′-di-tert-pentyldiphenylamine,p,p′-dioctyldiphenylamine, p,p′-dinonyldiphenylamine,p,p′-didecyldiphenylamine, p,p′-didodecyldiphenylamine,p,p′-distyryldiphenylamine, p,p′-dimethoxydiphenylamine,4,4′-bis(4-α,α-dimethylbenzoyl)diphenylamine, p-isopropoxydiphenylamine,dipyridylamine; phenothiazine based antioxidants such as phenothiazine,N-methylphenothiazine, N-ethylphenothiazine, 3,7-dioctylphenothiazine,phenothiazine carboxylic acid ester, and phenoselenazine;bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate (trade name “Tinuvin770” manufactured by BASF SE);[(4-methoxyphenyl)-methylene]-bis(1,2,2,6,6-pentamethyl-4-piperidinyl)malonate (trade name “Hostavin PR31” manufactured by Clariant AG); andthe like.

The sulfur based antioxidant is an antioxidant having a sulfur atom inthe molecule.

Examples of the sulfur based antioxidant include, for example, dialkylthiodipropionate compounds such as dilauryl, dimyristyl, or distearylthiodipropionate (“SUMILIZER TPM” (trade name, manufactured by SumitomoChemical Co., Ltd.), and the like); β-alkylmercaptopropionic acid estercompounds of polyols such astetrakis[methylene(3-dodecylthio)propionate]methane,tetrakis[methylene(3-laurylthio)propionate]methane;2-mercaptobenzimidazole; and the like.

The phenol based antioxidant is an antioxidant having a phenolic hydroxygroup in the molecule. In the present specification, a phosphorus-phenolbased antioxidant that has both phenolic hydroxy group and phosphoricacid ester structure or phosphorous acid ester structure is classifiedas a phenol based antioxidant.

Examples of the phenol based antioxidant include, for example,1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butane,4,4′-butylidenebis(3-methyl-6-tert-butylphenol),1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene,2-tert-butyl-6-(3-tert-butyl-2-hydroxy-5-methylbenzyl)-4-methylphenylacrylate,(tetrakis[methylene-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]methane,pentaerythritoltetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], octadecyl3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (“Irganox 1076” (tradename, manufactured by BASF SE)),3,3′,3″,5,5′,5″-hexa-tert-butyl-a,a′,a″-(mesitylen-2,4,6-triyl)tri-p-crezol,1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione,1,3,5-tris((4-tert-butyl-3-hydroxy-2,6-xylyl)methyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione,thiodiethylenebis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate],benzenepropanoic acid, 3,5-bis(1,1-dimethylethyl)-4-hydroxy C7-C9 sidechain alkyl ester, 4,6-bis(octylthiomethyl)-o-crezol,2,4-bis(n-octylthio)-6-(4-hydroxy-3′,5′-di-tert-butylanilino)-1,3,5-triazine,3,9-bis(2-(3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy)-1,1-dimethylethyl)-2,4,8,10-tetraoxaspiro(5,5)undecane(manufactured by ADEKA CORPORATION, trade name “ADEKASTAB AO-80”),triethylene glycolbis[3-(3-tert-butyl-5-methyl-4-hydroxyphenyl)propionate],4,4′-thiobis(6-tert-butyl-3-methylphenol),tris-(3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate,1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanurate,1,6-hexanediol bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate],N,N′-hexamethylenebis(3,5-di-tert-butyl-4-hydroxy-hydrocinnamamide),1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene,1,6-hexanediol bis-[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate],2,2′-methylenebis(4-methyl-6-tert-butylphenol),1,3,5-tris(4-hydroxybenzyl)benzene,6,6′-di-tert-butyl-4,4′-butylidenedi-m-cresol (manufactured by ADEKACORPORATION, trade name “ADEKASTAB AO-40”), “Irganox 3125” (trade name,manufactured by BASF SE), “SUMILIZER BHT” (trade name, manufactured bySumitomo Chemical Co., Ltd.), “SUMILIZER GA-80” (trade name,manufactured by Sumitomo Chemical Co., Ltd.), “SUMILIZER GS” (tradename, manufactured by Sumitomo Chemical Co., Ltd.), “Cyanox 1790” (tradename, manufactured by Cytec Industries Inc.), vitamin E (manufactured byEisai Co., Ltd.), and the like.

Examples of the phosphorus-phenol based antioxidant include, forexample,2,10-dimethyl-4,8-di-tert-butyl-6-[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propoxy]-12H-dibenzo[d,g][1,3,2]dioxaphosphocin,2,4,8,10-tetra-tert-butyl-6-[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propoxy]dibenzo[d,f][1,3,2]dioxaphosphepin,2,4,8,10-tetra-tert-butyl-6-[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyloxy]-dibenzo[d,f][1,3,2]dioxaphosphepin(manufactured by Sumitomo Chemical Co., Ltd., trade name “SUMILIZERGP”), and the like.

The phosphorus based antioxidant is an antioxidant having a phosphoricacid ester structure or phosphorous acid ester structure.

Examples of the phosphorus based antioxidant include, for example,diphenyl isooctyl phosphite,2,2′-methylenebis(4,6-di-tert-butylphenyl)octyl phosphite, diphenylisodecyl phosphite, diphenyl isodecyl phosphite, triphenyl phosphate,tributyl phosphate, diisodecyl pentaerythritol diphosphite, distearylpentaerythritol diphosphite, cyclic neopentanetetraylbis(2,4-di-tert-butylphenyl)phosphite, cyclic neopentanetetraylbis(2,6-di-tert-butylphenyl)phosphite, cyclic neopentanetetraylbis(2,6-di-tert-butyl-4-methylphenyl)phosphite,6-[3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propoxy]-2,4,8,10-tetra-tert-butylbenzo[d,f][1,3,2]dioxaphosphepin,tris(nonylphenyl) phosphite (manufactured by ADEKA CORPORATION, tradename “ADEKASTAB 1178”), tris(mono- & dinonylphenyl mixed) phosphite,diphenyl mono(tridecyl) phosphite,2,2′-ethylidenebis(4,6-di-tert-butylphenol)fluorophosphite, phenyldiisodecyl phosphite, tris(2-ethylhexyl) phosphite, tris(isodecyl)phosphite, tris(tridecyl) phosphite, tris(2,4-di-tert-butylphenyl)phosphite,tetrakis(2,4-di-tert-butylphenyl)-4,4′-biphenylene-di-phosphonite,4,4′-isopropylidene diphenyl tetraalkyl (C12-C15) diphosphite,4,4′-butylidenebis(3-methyl-6-tert-butylphenyl)-ditridecyl phosphite,bis(nonylphenyl)pentaerythritol diphosphite,bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite, cyclicneopentanetetrayl bis(2,6-di-tert-butyl-4-methylphenyl-phosphite),1,1,3-tris(2-methyl-4-ditridecyl phosphite-5-tert-butylphenyl)butane,tetrakis(2,4-di-tert-butyl-5-methylphenyl)-4,4′-biphenylenediphosphonite, tri-2-ethylhexyl phosphite, triisodecyl phosphite,tristearyl phosphite, phenyl diisodecyl phosphite, trilauryltrithiophosphite, distearylpentaerythritol diphosphite,tris(nonylphenyl) phosphite,tris[2-[[2,4,8,10-tetra-tert-butyldibenzo[d,f][1,3,2]dioxaphosphin-6-yl]oxy]ethyl]amine,bis(2,4-bis(1,1-dimethylethyl)-6-methylphenyl)ethyl ester phosphorousacid,3,9-bis(2,6-di-tert-butyl-4-methylphenoxy)-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane,bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite,2,2′-methylenebis(4,6-di-tert-butyl-1-phenyloxy) (2-ethylhexyloxy)phosphorus, triphenyl phosphite,4,4′-butylidene-bis(3-methyl-6-tert-butylphenylditridecyl)phosphite,octadecyl phosphite, 9,10-dihydro-9-oxa-10-phosphaphenanthrene 10-oxide,10-(3,5-di-tert-butyl-4-hydroxybenzyl)-9,10-dihydro-9-oxa-10-phosphaphenanthrene10-oxide, 10-decyloxy-9,10-dihydro-9-oxa-10-phosphaphenanthrene10-oxide, 2,2-methylenebis(4,6-di-tert-butylphenyl)octyl phosphite,tetrakis(2,4-di-tert-butylphenyl) [1,1-biphenyl]-4,4′-diylbisphosphonite, bis[2,4-bis(1,1-dimethylethyl)-6-methylphenyl]ethylester phosphonic acid, “ADEKASTAB 329K” (trade name, manufactured byADEKA CORPORATION), “ADEKASTAB PEP36” (trade name, manufactured by ADEKACORPORATION), “ADEKASTAB PEP-8” (trade name, manufactured by ADEKACORPORATION), “Sandstab P-EPQ” (trade name, manufactured by ClariantAG), “Weston 618” (trade name, manufactured by GE Specialty ChemicalsInc.), “Weston 619G” (trade name, manufactured by GE Specialty ChemicalsInc.), “ULTRANOX 626” (trade name, manufactured by GE SpecialtyChemicals Inc.), and the like.

The antioxidant (D) comprising a phenol based antioxidant (which may bea phosphorus-phenol based antioxidant) is advantageous in improving thestability of the curable composition over time. When the curablecomposition comprises a phenol based antioxidant, the decrease in thequantum yield due to heat described above can be suppressed, and theeffect of suppressing a decrease in the quantum yield of the curablecomposition over time can be enhanced as well. The amount of change inthe quantum yield of the curable composition over time can be calculatedas the percentage of the quantum yield “QY (after stability over timetest)” (%) of the curable composition before curing after still standingto the quantum yield “QY (initial)” (%) of the curable compositionbefore curing, and is represented as the QY maintenance rate B by thefollowing expression.QY maintenance rate B (%)=100×QY (after stability over time test)/QY(initial)

When the QY maintenance rate B is higher, the stability of the curablecomposition over time (storage stability) tends to be higher, which isthus preferable. The QY maintenance rate B is preferably 40% or more,more preferably 50% or more, further preferably 60% or more, and evenfurther preferably 70% or more. QY (initial) is preferably 40% or more,more preferably 50% or more, further preferably 60% or more, evenfurther preferably 65% or more, and particularly preferably 80% or more.

Although the specific method for measuring QY (after stability over timetest) and QY (initial) follows the description in [Examples], which willbe mentioned below, for example, for a sample (applied layer) obtainedby applying the curable composition before curing onto glass, thequantum yield “QY (initial)” (%) may be measured at an excitation lightof 450 nm, at room temperature, and under the atmosphere, using anabsolute PL quantum yield spectrometer, and then, after standing thecurable composition before curing still for a predetermined period oftime and then fabricating a sample (applied layer) from that curablecomposition in the same manner, the quantum yield “QY (after stabilityover time test)” (%) may be measured in the same manner as describedabove. Examples of the still standing (stability over time test)include, for example, a method in which the curable composition beforecuring is retained in a sample bottle in the air and at a temperature of23° C. for 12 days.

The content of the antioxidant (D) in the curable composition is, fromthe viewpoint of suppressing the decrease in the quantum yield due toheat described above and from the viewpoint of improving the stabilityof the curable composition over time, for example, 0.1% by mass or moreand 20% by mass or less in 100% by mass of the solid content of thecurable composition, preferably 0.2% by mass or more and 10% by mass orless, and more preferably 0.3% by mass or more and 5% by mass or less.

[5] Quantum Dot (E)

The curable composition can further comprise a fluorescent materialother than the fluorescent particle (A), and preferably, can furthercomprise a quantum dot (E). When the curable composition furthercomprises the quantum dot (E) in addition to the fluorescent particle(A), the color of emitted light emitted by the curable composition orthe cured film thereof can be more readily adjusted and a higher colorgamut can also be achieved in a display apparatus or the like equippedwith such a cured film.

The curable composition may comprise only one kind of quantum dot (E) ormay comprise two or more kinds thereof.

The quantum dot (E) is not particularly limited as long as it is aquantum dot particle that is capable of emitting fluorescence in thevisible light wavelength region, and it can be selected from the groupconsisting of, for example, II-VI semiconductor compounds; III-Vsemiconductor compounds; IV-VI semiconductor compounds; group IVelements or compounds containing the same; and combinations thereof.These quantum dots may be used alone, or two or more kinds thereof maybe used in mixture.

The II-VI semiconductor compounds can be selected from the groupconsisting of: binary compounds selected from the group consisting ofCdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, and mixturesthereof; ternary compounds selected from the group consisting of CdSeS,CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS,CdZnSe, CdZnSe, CdHgS, CdHgSe, CdHgSe, HgZnS, HgZnSe, HgZnSe, andmixtures thereof; and quaternary compounds selected from the groupconsisting of CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe,HgZnSeS, HgZnSeTe, HgZnSTe, and mixtures thereof.

The III-V semiconductor compounds described above can be selected fromthe group consisting of: binary compounds selected from the groupconsisting of GaN, GaP, GaAs, GaSb, AlN, Alp, AlAs, AlSb, InN, InP,InAs, InSb, and mixtures thereof; ternary compounds selected from thegroup consisting of GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs,AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP, andmixtures thereof; and quaternary compounds selected from the groupconsisting of GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs,GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, InAlPSb,and mixtures thereof.

The IV-VI semiconductor compounds described above can be selected fromthe group consisting of: binary compounds selected from the groupconsisting of SnS, SnSe, SnTe, PbS, PbSe, PbTe, and mixtures thereof;ternary compounds selected from the group consisting of SnSeS, SnSeTe,SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, and mixturesthereof; and quaternary compounds selected from the group consisting ofSnPbSSe, SnPbSeTe, SnPbSTe, and mixtures thereof.

The group IV elements or compounds containing the same described abovecan be selected from the group consisting of: element compounds selectedfrom the group consisting of Si, Ge, and mixtures thereof; and binarycompounds selected from the group consisting of SiC, SiGe, and mixturesthereof.

The quantum dot (E) can have a homogeneous single structure; a dualstructure such as core-shell or gradient structure; or a mixed structurethereof.

In the core-shell dual structure, the substances constituting the coreand the shell can be composed of the aforementioned semiconductorcompounds that are different from each other. For example, the coredescribed above can comprise one or more substances selected from thegroup consisting of, without limitations, CdSe, CdS, ZnS, ZnSe, ZnTe,CdTe, CdSeTe, CdZnS, PbSe, AgInZnS, HgS, HgSe, HgTe, GaN, GaP, GaAs,InP, InAs, and ZnO.

For example, the shell described above can comprise one or moresubstances selected from the group consisting of, without limitations,CdSe, ZnSe, ZnS, ZnTe, CdTe, PbS, TiO, SrSe, and HgSe.

Just as a coloring photosensitive resin composition used in theproduction of ordinary color filters comprises a red, green, or bluecolorant for embodying the color phase, particles of photoluminescentquantum dots can be classified into a red quantum dot particle, a greenquantum dot particle, and a blue quantum dot particle.

The quantum dot (E) can be a red quantum dot particle, a green quantumdot particle, or a blue quantum dot particle.

Although the diameter of the quantum dot (E) is not particularlylimited, red, green, and blue quantum dot particles can be classifiedaccording to the particle diameter, with the particle diameter beingsmaller in the order of red, green, and blue.

Specifically, the red quantum dot particle can have a particle diameterof 5 nm or more and 10 nm or less, the green quantum dot particle canhave a particle diameter of greater than 3 nm and 5 nm or less, and theblue quantum dot particle can have a particle diameter of 1 nm or moreand 3 nm or less.

Upon irradiation of light, the red quantum dot particle releases redlight, the green quantum dot particle releases green light, and the bluequantum dot particle releases blue light.

The quantum dot (E) can be synthesized by a wet chemical process, ametal organic chemical vapor deposition process, or a molecular beamepitaxy process. The wet chemical process is a method in which aprecursor material is placed in an organic solvent to grow particles.During crystal growth, the organic solvent naturally coordinates to thesurface of the quantum dot crystal and acts as a dispersing agent toregulate crystal growth, and thus, the growth of nanoparticles can becontrolled through an easier and less expensive process compared tovapor deposition methods such as metal organic chemical vapor deposition(MOCVD) and molecular beam epitaxy (MBE).

In one preferable embodiment, the curable composition comprises afluorescent particle (A) and a quantum dot (E), wherein the fluorescentparticle (A) is a green fluorescent particle and the quantum dot (E) isa red quantum dot particle.

The content of the quantum dot (E) in the curable composition is notparticularly limited and can be selected in consideration of a desiredcolor of emitted light and the like. The content of the quantum dot (E)in 100% by mass of the curable composition is preferably 50% by mass orless, more preferably 5% by mass or less, and further preferably 1% bymass or less. In addition, from the viewpoint of obtaining a goodemission intensity, the content is preferably 0.0001% by mass or more,more preferably 0.0005% by mass or more, and further preferably 0.001%by mass or more.

The upper limits and the lower limits described above can be arbitrarilycombined.

The content of the quantum dot (E) in the curable composition isnormally 0.0001% by mass or more and 50% by mass or less in 100% by massof the curable composition.

The content of the quantum dot (E) in the curable composition ispreferably 0.0001% by mass or more and 5% by mass or less in 100% bymass of the curable composition, and is more preferably 0.0005% by massor more and 2% by mass or less.

A composition in which the content of the quantum dot (E) is within therange described above is preferable in that the aggregation of thequantum dot (E) is less likely to occur and the light emittingproperties are also demonstrated well.

[6] Dispersing Agent

The curable composition may comprise a dispersing agent. As a result ofthis, the dispersibility of the fluorescent particle (A) containing aperovskite compound to the photopolymerizable compound (B) can be madewell.

The curable composition may comprise only one kind of dispersing agentor may comprise two or more kinds thereof.

Examples of the dispersing agent include a dispersing agent containing acompound having a polar functional group that is adsorbed onto thefluorescent particle (A) to stabilize the dispersion of the fluorescentparticle (A) to the photopolymerizable compound (B).

The compound having a polar functional group described above is, fromthe viewpoint of enhancing the dispersibility of the fluorescentparticle (A) to the photopolymerizable compound (B), at least one kindof compound selected from the group consisting of phosphoric acidcompounds, carboxylic acid compounds, sulfonic acid compounds, primaryto tertiary amine compounds, quaternary ammonium compounds, and thiolcompounds, and the curable composition of the present inventioncomprises at least one kind of compound selected from the groupconsisting of these compounds.

Among the above, from the viewpoint of enhancing the dispersibility ofthe fluorescent particle (A) to the photopolymerizable compound (B) andfrom the viewpoint of increasing the quantum yield of the curablecomposition itself, the compound having a polar functional groupdescribed above is preferably at least one kind of compound selectedfrom the group consisting of phosphoric acid compounds, carboxylic acidcompounds, and tertiary amine compounds.

In the present specification, the phosphoric acid compound means acompound having one or two or more polar functional groups representedby *—O—P(═O)(OR′)(OR″). In the formula, * represents a bonding hand withanother structural moiety in the phosphoric acid compound. R′ and R″each independently represent a hydrogen atom or a monovalent organicgroup. The polar functional group represented by the above formula mayform a salt.

The carboxylic acid compound means a compound having one or two or morecarboxy groups. The carboxy group may form a salt.

The sulfonic acid compound means a compound having one or two or moresulfo groups. The sulfo group may form a salt.

The primary to tertiary amine compound means a compound having one ortwo or more polar functional groups represented by the followingformula.

In the formula, * represents a bonding hand with another structuralmoiety in the primary to tertiary amine compound. R¹ and R² eachindependently represent a hydrogen atom or a monovalent organic group.When R¹ and R² are hydrogen atoms, such a compound is a primary aminecompound; when one of R¹ and R² is a monovalent organic group, such acompound is a secondary amine compound; and when R¹ and R² aremonovalent organic groups, such a compound is a tertiary amine compound.The polar functional group represented by the above formula may form asalt.

The quaternary ammonium compound means a compound having one or two ormore polar functional groups represented by the following formula.

In the formula, * represents a bonding hand with another structuralmoiety in the quaternary ammonium compound. R¹¹, R²², and R³³ eachindependently represent a hydrogen atom or a monovalent organic group.The polar functional group represented by the above formula may form asalt.

The thiol compound means a compound having one or two or more —SHgroups.

The compound having a polar functional group described above is, forexample, a resin having the polar functional group described above. Theresin backbone may be, for example, one containing a polyurethanebackbone, a polyester backbone, a poly(meth)acrylic backbone, apolyether backbone, a polyamide backbone, an aliphatic backbone, or thelike in the main chain or side chain.

In particular, from the viewpoint of increasing the quantum yield of thecurable composition itself, the compound having a polar functional groupdescribed above preferably contains at least one bond selected from thegroup consisting of an ether bond and an ester bond in the molecularchain, and when the compound having a polar functional group describedabove is a resin, such a resin preferably contains at least one bondselected from the group consisting of an ether bond and an ester bond inthe polymer chain, and more preferably contains at least one selectedfrom the group consisting of a polyether chain and a polyester chain inthe molecular chain.

The polyether backbone is preferably a poly(oxyalkylene) chain from theviewpoint of increasing the quantum yield of the curable compositionitself.

The polar sites described above, such as an ether bond and an esterbond, as well as a polyether chain and a polyester chain, effectivelyserve as a site that exhibits compatibility with the photopolymerizablecompound (B), particularly a photopolymerizable compound (B) with a highpolarity, which can further enhance the dispersibility of thefluorescent particle (A) to the photopolymerizable compound (B).

As the resin type dispersing agent comprising a resin having the polarfunctional group described above, commercial products can be used aswell.

Examples of such commercial products include:

DISPERBYK-101, 102, 103, 106, 107, 108, 109, 110, 111, 116, 118, 130,140, 154, 161, 162, 163, 164, 165, 166, 170, 171, 174, 180, 181, 182,183, 184, 185, 190, 192, 2000, 2001, 2020, 2025, 2050, 2070, 2095, 2150,2155; ANTI-TERRA-U, U100, 203, 204, 250; BYK-P104, P104S, P105, 220S,and 6919; BYK-LPN6919 and 21116; LACTIMON and LACTIMON-WS; Bykumen; andthe like, manufactured by BYK Japan KK.;

SOLSPERSE-3000, 9000, 13000, 13240, 13650, 13940, 16000, 17000, 18000,20000, 21000, 24000, 26000, 27000, 28000, 31845, 32000, 32500, 32550,33500, 32600, 34750, 35100, 36600, 38500, 41000, 41090, 53095, 55000,76500, and the like, manufactured by Lubrizol Japan Limited;

EFKA-46, 47, 48, 452, 4008, 4009, 4010, 4015, 4020, 4047, 4050, 4055,4060, 4080, 4400, 4401, 4402, 4403, 4406, 4408, 4300, 4310, 4320, 4330,4340, 450, 451, 453, 4540, 4550, 4560, 4800, 5010, 5065, 5066, 5070,7500, 7554, 1101, 120, 150, 1501, 1502, 1503, and the like, manufacturedby BASF SE;

AJISPER PA111, PB711, PB821, PB822, and PB824, manufactured by AjinomotoFine-Techno Co., Inc.; and the like.

The content of the dispersing agent in the curable composition is, fromthe viewpoint of enhancing the dispersibility of the fluorescentparticle (A) to the photopolymerizable compound (B), for example, 0.1parts by mass or more and 20 parts by mass or less relative to 1 part bymass of the fluorescent particle, preferably 0.2 parts by mass or moreand 10 parts by mass or less, and more preferably 0.3 parts by mass ormore and 5 parts by mass or less.

[7] Solvent

The curable composition can comprise a solvent from the viewpoint of theapplication properties of the curable composition, the dispersibility ofthe fluorescent particle (A) and/or the quantum dot (E), and the like.

Examples of the solvent include, for example, esters such as methylformate, ethyl formate, propyl formate, pentyl formate, methyl acetate,ethyl acetate, and pentyl acetate; ketones such as γ-butyrolactone,N-methyl-2-pyrrolidone, acetone, dimethyl ketone, diisobutyl ketone,cyclopentanone, cyclohexanone, and methylcyclohexanone; ethers such asdiethyl ether, methyl tert-butyl ether, diisopropyl ether,dimethoxymethane, dimethoxyethane, 1,4-dioxane, 1,3-dioxolane,4-methyldioxolane, tetrahydrofuran, methyltetrahydrofuran, anisole, andphenetole; alcohols such as methanol, ethanol, 1-propanol, 2-propanol,1-butanol, 2-butanol, tert-butanol, 1-pentanol, 2-methyl-2-butanol,methoxypropanol, diacetone alcohol, cyclohexanol, 2-fluoroethanol,2,2,2-trifluoroethanol, and 2,2,3,3-tetrafluoro-1-propanol; glycolethers such as ethylene glycol monomethyl ether, ethylene glycolmonoethyl ether, ethylene glycol monobutyl ether, ethylene glycolmonoethyl ether acetate, and triethylene glycol dimethyl ether; organicsolvents having an amide group such as N,N-dimethylformamide, acetamide,and N,N-dimethylacetamide; organic solvents having a nitrile group suchas acetonitrile, isobutyronitrile, propionitrile, andmethoxyacetonitrile; organic solvents having a carbonate group such asethylene carbonate and propylene carbonate; organic solvents having ahalogenated hydrocarbon group such as methylene chloride and chloroform;organic solvents having a hydrocarbon group such as n-pentane,cyclohexane, n-hexane, benzene, toluene, and xylene; dimethyl sulfoxide;and the like.

Among the above, preferable are esters such as methyl formate, ethylformate, propyl formate, pentyl formate, methyl acetate, ethyl acetate,and pentyl acetate; ketones such as γ-butyrolactone,N-methyl-2-pyrrolidone, acetone, dimethyl ketone, diisobutyl ketone,cyclopentanone, cyclohexanone, and methylcyclohexanone; ethers such asdiethyl ether, methyl tert-butyl ether, diisopropyl ether,dimethoxymethane, dimethoxyethane, 1,4-dioxane, 1,3-dioxolane,4-methyldioxolane, tetrahydrofuran, methyltetrahydrofuran, anisole, andphenetole; organic solvents having a nitrile group such as acetonitrile,isobutyronitrile, propionitrile, and methoxyacetonitrile; organicsolvents having a carbonate group such as ethylene carbonate andpropylene carbonate; organic solvents having a halogenated hydrocarbongroup such as methylene chloride and chloroform; and organic solventshaving a hydrocarbon group such as n-pentane, cyclohexane, n-hexane,benzene, toluene, and xylene because they have low polarity and arethought to be unlikely to dissolve the fluorescent particle (A), andmore preferable are organic solvents having a halogenated hydrocarbongroup such as methylene chloride and chloroform; and organic solventshaving a hydrocarbon group such as n-pentane, cyclohexane, n-hexane,benzene, toluene, and xylene.

When the curable composition comprises a solvent, the content thereof isnot particularly limited, but for example, it is adjusted such that thesolid content in the curable composition becomes 1% by mass or more and99% by mass or less. The range described above is preferably 5% by massor more and 95% by mass or less.

(8) Additional Components

The curable composition can further comprise additional components otherthan the above, if required.

Examples of the additional components include, for example, resins(polymer compounds), leveling agents, light scattering agents (inorganicparticles and the like), fillers, adhesion promoting agents, UVabsorbers, anti-aggregation agents, curing agents, and the like.

The curable composition may comprise only one kind of additionalcomponent or may comprise two or more kinds thereof.

<Method for Producing Curable Composition>

(1) Method for Producing Perovskite Compound

The perovskite compound can be produced with reference to the knownliteratures (Nano Lett. 2015, 15, 3692-3696; ACS Nano, 2015, 9,4533-4542), for example, by the method mentioned below.

(1-1) First Embodiment of Method for Producing Perovskite Compound withA, B, and X as the Components Thereof

A method for producing a perovskite compound according to the firstembodiment includes the steps of:

dissolving a component B, a component X, and a component A in a solventx to obtain a solution g; and

mixing the obtained solution g with a solvent y, in which a perovskitecompound has a lower solubility compared to that in the solvent x usedin the step of obtaining the solution g.

More specifically, such a production method may be a production methodincluding the steps of:

dissolving a compound comprising a component B and component X and acompound comprising a component A or a component A and component X in asolvent x to obtain a solution g; and

mixing the obtained solution g with a solvent y, in which a perovskitecompound has a lower solubility compared to that in the solvent x usedin the step of obtaining the solution g.

Hereinafter, a production method will be described that includes thesteps of: dissolving a compound comprising a component B and component Xand a compound comprising a component A or a component A and component Xin a solvent x to obtain a solution g; and mixing the obtained solutiong with a solvent y, in which a perovskite compound has a lowersolubility compared to that in the solvent x used in the step ofobtaining the solution g.

Note that the solubility refers to the solubility at the temperaturewhere the mixing step is performed.

Such a production method preferably includes a step of adding a cappingligand from the viewpoint of enabling stable dispersion of theperovskite compound. The capping ligand is preferably added before themixing step mentioned above, and it may be added to the solution g inwhich the component A, component B, and component X have been dissolved,or it may be added to the solvent y, in which the perovskite compoundhas a lower solubility compared to that in the solvent x used in thestep of obtaining the solution g, or may be added to both solvent x andsolvent y.

The production method preferably includes a step of removing coarseparticles by an approach such as centrifugation or filtration after themixing step mentioned above. The size of the coarse particles to beremoved by the removing step described above is preferably 10 μm ormore, more preferably 1 μm or more, and further preferably 500 nm ormore.

The step of mixing the solution g with the solvent y may be a step of:

(I) adding the solution g dropwise to the solvent y; or

(II) adding the solvent y dropwise to the solution g.

However, from the viewpoint of enhancing the dispersibility of thefluorescent particle (A), (I) is preferable.

It is preferable to carry out stirring during the dropwise addition fromthe viewpoint of enhancing the dispersibility of the fluorescentparticle (A).

In the step of mixing the solution g and the solvent y, there is noparticular limitation on the temperature, but from the viewpoint ofensuring the ease of precipitation of the fluorescent particle (A), itis preferable to be in the range of −20° C. or higher and 40° C. orlower, and more preferable to be in the range of −5° C. or higher and30° C. or lower.

Although the solvents x and y are not particularly limited, examplesthereof include, for example, two kinds of solvents selected from thegroup consisting of alcohols such as methanol, ethanol, 1-propanol,2-propanol, 1-butanol, 2-butanol, tert-butanol, 1-pentanol,2-methyl-2-butanol, methoxypropanol, diacetone alcohol, cyclohexanol,2-fluoroethanol, 2,2,2-trifluoroethanol, and2,2,3,3-tetrafluoro-1-propanol; glycol ethers such as ethylene glycolmonomethyl ether, ethylene glycol monoethyl ether, ethylene glycolmonobutyl ether, ethylene glycol monoethyl ether acetate, andtriethylene glycol dimethyl ether; organic solvents having an amidegroup such as N,N-dimethylformamide, acetamide, andN,N-dimethylacetamide; esters such as methyl formate, ethyl formate,propyl formate, pentyl formate, methyl acetate, ethyl acetate, andpentyl acetate; ketones such as γ-butyrolactone, N-methyl-2-pyrrolidone,acetone, dimethyl ketone, diisobutyl ketone, cyclopentanone,cyclohexanone, and methylcyclohexanone; ethers such as diethyl ether,methyl tert-butyl ether, diisopropyl ether, dimethoxymethane,dimethoxyethane, 1,4-dioxane, 1,3-dioxolane, 4-methyldioxolane,tetrahydrofuran, methyltetrahydrofuran, anisole, and phenetole; organicsolvents having a nitrile group such as acetonitrile, isobutyronitrile,propionitrile, and methoxyacetonitrile; organic solvents having acarbonate group such as ethylene carbonate and propylene carbonate;organic solvents having a halogenated hydrocarbon group such asmethylene chloride and chloroform; and organic solvents having ahydrocarbon group such as n-pentane, cyclohexane, n-hexane, benzene,toluene, and xylene; and dimethyl sulfoxide.

As the solvent x used in the step of obtaining the solution g, a solventin which the perovskite compound has a high solubility is preferable,and when that step is carried out at room temperature (10° C. to 30° C.)examples of the solvent x include, for example, alcohols such asmethanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol,tert-butanol, 1-pentanol, 2-methyl-2-butanol, methoxypropanol, diacetonealcohol, cyclohexanol, 2-fluoroethanol, 2,2,2-trifluoroethanol, and2,2,3,3-tetrafluoro-1-propanol; glycol ethers such as ethylene glycolmonomethyl ether, ethylene glycol monoethyl ether, ethylene glycolmonobutyl ether, ethylene glycol monoethyl ether acetate, andtriethylene glycol dimethyl ether; organic solvents having an amidegroup such as N,N-dimethylformamide, acetamide, andN,N-dimethylacetamide; and dimethyl sulfoxide.

As the solvent y used in the mixing step, a solvent in which theperovskite compound has a low solubility is preferable, and when thatstep is carried out at room temperature (10° C. to 30° C.), examples ofthe solvent y include, for example, esters such as methyl formate, ethylformate, propyl formate, pentyl formate, methyl acetate, ethyl acetate,and pentyl acetate; ketones such as γ-butyrolactone,N-methyl-2-pyrrolidone, acetone, dimethyl ketone, diisobutyl ketone,cyclopentanone, cyclohexanone, and methylcyclohexanone; ethers such asdiethyl ether, methyl tert-butyl ether, diisopropyl ether,dimethoxymethane, dimethoxyethane, 1,4-dioxane, 1,3-dioxolane,4-methyldioxolane, tetrahydrofuran, methyltetrahydrofuran, anisole, andphenetole; organic solvents having a nitrile group such as acetonitrile,isobutyronitrile, propionitrile, and methoxyacetonitrile; organicsolvents having a carbonate group such as ethylene carbonate andpropylene carbonate; organic solvents having a halogenated hydrocarbongroup such as methylene chloride and chloroform; and organic solventshaving a hydrocarbon group such as n-pentane, cyclohexane, n-hexane,benzene, toluene, and xylene.

In the two kinds of solvents with different solubility, the differencein solubility is preferably 100 μg per 100 g of solvent or more and 90 gper 100 g of solvent or less, and is more preferably 1 mg per 100 g ofsolvent or more and 90 g per 100 g of solvent or less.

From the viewpoint of setting the difference in solubility to 100 μg per100 g of solvent or more and 90 g per 100 g of solvent or less, when themixing step is performed at room temperature (10° C. to 30° C.), forexample, it is preferable that the solvent x should be an organicsolvent having an amide group such as N,N-dimethylacetamide or dimethylsulfoxide and the solvent y should be an organic solvent having ahalogenated hydrocarbon group such as methylene chloride or chloroform;or an organic solvent having a hydrocarbon group such as n-pentane,cyclohexane, n-hexane, benzene, toluene, or xylene.

As a method for taking out the fluorescent particle (A) containing theperovskite compound from the obtained dispersion liquid containing theperovskite compound, mention may be made of a method in whichsolid-liquid separation is carried out, thereby recovering only thefluorescent particle (A).

Examples of the solid-liquid separation method mentioned above include amethod of filtration and the like, a method of utilizing evaporation ofthe solvent, and the like.

(1-2) Second Embodiment of Method for Producing Perovskite Compound withA, B, and X as the Components Thereof

A method for producing a perovskite compound according to the secondembodiment is a production method including the steps of:

adding a component B, a component X, and a component A to a solvent z athigh temperature to dissolve them, thereby obtaining a solution h; and

cooling the obtained solution h.

More specifically, such a production method may be a production methodincluding the steps of:

adding a compound comprising a component B and component X and acompound comprising a component A or a component A and component X to asolvent z at high temperature to dissolve them, thereby obtaining asolution h; and

cooling the obtained solution h.

The step of obtaining a solution h may be a step in which, after addinga compound comprising a component B and component X and a compoundcomprising a component A or a component A and component X to a solventz, the temperature is raised, thereby obtaining a solution h.

In such a production method, the fluorescent particle (A) containing theperovskite compound can be precipitated by the difference in solubilitydue to the difference in temperature.

Such a production method preferably includes a step of adding a cappingligand from the viewpoint of enabling stable dispersion of theperovskite compound. The capping ligand is preferably contained in thesolution h before the cooling step mentioned above.

The production method preferably includes a step of removing coarseparticles by an approach such as centrifugation or filtration after thecooling step. The size of the coarse particles to be removed by theremoving step described above is preferably 10 μm or more, morepreferably 1 μm or more, and further preferably 500 nm or more.

The solvent z at high temperature is any solvent as long as it is asolvent at a temperature where the compound comprising the component Band component X and the compound comprising the component A or thecomponent A and component X are dissolved, and for example, a solventwith a boiling point of 60° C. or higher and 600° C. or lower ispreferable, and a solvent with a boiling point of 80° C. or higher and400° C. or lower is more preferable.

The cooling temperature is preferably −20° C. or higher and 50° C. orlower, and is more preferably −10° C. or higher and 30° C. or lower.

Although the solvent z is not particularly limited as long as it is asolvent that can dissolve the compound comprising the component B andcomponent X and the compound comprising the component A or the componentA and component X, examples thereof include, for example, esters such asmethyl formate, ethyl formate, propyl formate, pentyl formate, methylacetate, ethyl acetate, and pentyl acetate; ketones such asγ-butyrolactone, N-methyl-2-pyrrolidone, acetone, dimethyl ketone,diisobutyl ketone, cyclopentanone, cyclohexanone, andmethylcyclohexanone; ethers such as diethyl ether, methyl tert-butylether, diisopropyl ether, dimethoxymethane, dimethoxyethane,1,4-dioxane, 1,3-dioxolane, 4-methyldioxolane, tetrahydrofuran,methyltetrahydrofuran, anisole, and phenetole; alcohols such asmethanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol,tert-butanol, 1-pentanol, 2-methyl-2-butanol, methoxypropanol, diacetonealcohol, cyclohexanol, 2-fluoroethanol, 2,2,2-trifluoroethanol, and2,2,3,3-tetrafluoro-1-propanol; glycol ethers such as ethylene glycolmonomethyl ether, ethylene glycol monoethyl ether, ethylene glycolmonobutyl ether, ethylene glycol monoethyl ether acetate, andtriethylene glycol dimethyl ether; organic solvents having an amidegroup such as N,N-dimethylformamide, acetamide, andN,N-dimethylacetamide; organic solvents having a nitrile group such asacetonitrile, isobutyronitrile, propionitrile, and methoxyacetonitrile;organic solvents having a carbonate group such as ethylene carbonate andpropylene carbonate; organic solvents having a halogenated hydrocarbongroup such as methylene chloride and chloroform; organic solvents havinga hydrocarbon group such as n-pentane, cyclohexane, n-hexane, benzene,toluene, and xylene; dimethyl sulfoxide; and 1-octadecene.

As a method for taking out the fluorescent particle (A) containing theperovskite compound from the obtained dispersion liquid containing theperovskite compound, mention may be made of a method in whichsolid-liquid separation is carried out, thereby recovering only thefluorescent particle (A).

Examples of the solid-liquid separation method mentioned above include amethod of filtration and the like, a method of utilizing evaporation ofthe solvent, and the like.

(2) Method for Producing Curable Composition

The curable composition can be prepared by mixing the fluorescentparticle (A), the photopolymerizable compound (B), thephotopolymerization initiator (C), and the antioxidant (D), as well asthe quantum dot (E), dispersing agent, solvent, and additionalcomponents, to be used as required.

<Film>

A film can be obtained by using the curable composition described above.

For example, a film can be formed by applying the curable composition toa substrate using a publicly known method such as a gravure coater, adip coater, a reverse coater, a wire bar coater, a die coater, or aninkjet method, and subjecting the substrate to a curing process byphotoirradiation.

There is no particular limitation on the light to be used for the curingtreatment, and light such as ultraviolet light and visible light can beused. Light with a wavelength of 150 to 800 nm is preferable, and lightwith a wavelength of 200 to 500 nm is more preferable.

As the light source, a low pressure mercury lamp, a high pressuremercury lamp, an ultra high pressure mercury lamp, a chemical lamp, alight emitting diode (LED) light source, an excimer laser generator, andthe like can be used, and active light rays having a wavelength of 300nm or more and 450 nm or less such as the i-line (365 nm), the h-line(405 nm), and the g-line (436 nm) can be preferably used. Also, ifrequired, the irradiated light may be adjusted through a spectral filtersuch as a long wavelength cut filter, a short wavelength cut filter, ora band pass filter.

The amount of exposure is preferably 1 mJ/cm² or more and 5000 mJ/cm² orless, more preferably 10 mJ/cm² or more and 2000 mJ/cm² or less, andfurther preferably 30 mJ/cm² or more and 500 mJ/cm² or less.

The film shape is not particularly limited, and can be any shape such assheet shape or bar shape.

The thickness of the film may be 0.01 μm or more and 1000 mm or less,may be 0.1 μm or more and 10 mm or less, and may be 1 μm or more and 1mm or less.

The film may be a single layer or multiple layers. In the case ofmultiple layers, the same kind of curable composition may be used foreach layer, or different kinds of curable compositions may be used foreach other.

<Laminated Body>

A laminated body according to the present invention has a plurality oflayers, and at least one layer is the film mentioned above.

Out of the plurality of layers that the laminated body has, as thelayers other than the film mentioned above, mention may be made of anylayer such as a substrate, a barrier layer, and a light scatteringlayer.

The shape of films to be laminated is not particularly limited, and canbe any shape such as sheet shape or bar shape.

(1) Substrate

Although there is no particular limitation on the substrate, it may be afilm, and from the viewpoint of extracting the emitted light, thesubstrate preferably has translucency, and is more preferablytransparent. As the material of the substrate, for example, a publiclyknown material such as a thermoplastic resin including polyethyleneterephthalate or glass can be used.

For example, in the laminated body, the film mentioned above may beprovided on the substrate.

FIG. 1 is a schematic sectional view illustrating one example of theconfiguration of a laminated body. In a laminated body 1 a illustratedin FIG. 1 , a film 10 composed of a cured product of the curablecomposition is provided between substrates 20 and 21.

The film 10 may be sealed by a sealing material.

(2) Barrier Layer

The laminated body may comprise a barrier layer from the viewpoint ofprotecting the film formed from the curable composition from water vaporin the outside air and air in the atmosphere.

Although there is no particular limitation on the barrier layer, fromthe viewpoint of extracting the emitted light, it preferably hastranslucency, and is more preferably transparent. As the material of thebarrier layer, for example, a publicly known material such as athermoplastic resin including polyethylene terephthalate or glass can beused.

(3) Light Scattering Layer

The laminated body may comprise a light scattering layer from theviewpoint of effectively utilizing the incident light.

Although there is no particular limitation on the light scatteringlayer, from the viewpoint of extracting the emitted light, it preferablyhas translucency, and is more preferably transparent.

As the light scattering layer, a publicly known light scattering layersuch as a layer containing a light scattering agent (light scatteringparticles) including silica particles or an amplification diffusion filmcan be used.

<Light Emitting Apparatus>

The display apparatus of the present invention may comprise a lightemitting apparatus. The light emitting apparatus comprises the filmdescribed above or the laminated body described above, and normally, inaddition to this, further comprises a light source. The light emittingapparatus is an apparatus for extracting light by irradiating the filmor laminated body, which is installed in the subsequent stage, withlight emitted from the light source to make the film or laminated bodyemit light. The light emitting apparatus can be further equipped withany layer such as a light reflective member, a brightness enhancementsection, a prism sheet, a light guide plate, and a medium material layerbetween elements.

(1) Light Source

Although there is no particular limitation on the light source, a lightsource having an emission wavelength of 600 nm or less is preferablefrom the viewpoint of causing the fluorescent particle (A) in the filmor laminated body to emit light. As the light source, for example, apublicly known light source such as a light emitting diode (LED)including a blue light emitting diode, a laser, and an EL can be used.

(2) Light Reflective Member

The light emitting apparatus may comprise a light reflective member (70in FIG. 2 ) from the viewpoint of directing light from the light sourcetowards the film or laminated body. Although there is no particularlimitation on the light reflective member, it may be a reflective film.

As the reflective film, for example, a publicly known reflective filmsuch as a reflective mirror, a film of reflective particles, areflective metal film, or a reflective body can be used.

(3) Brightness Enhancement Section

The light emitting apparatus may comprise a brightness enhancementsection from the viewpoint of reflecting a part of the light backtowards the direction in which the light was transmitted.

(4) Prism Sheet

The light emitting apparatus may have a prism sheet. The prism sheettypically has a base material section and a prism section. The basematerial section may be omitted, depending on the adjacent members.

The prism sheet can be pasted together with the adjacent members via anyappropriate adhesive layer (for example, an adhesive layer or a stickerlayer). The prism sheet is configured to have a plurality of unit prismsthat are convex in parallel on the side opposite to the visible side(rear side). By arranging the convex sections of the prism sheet towardthe rear side, the light that passes through the prism sheet is morelikely to be focused.

Also, when the convex sections of the prism sheet are arranged towardthe rear side, there is less light reflected without incident on theprism sheet compared to the case where the convex sections are arrangedtoward the visible side, and a display apparatus with high brightnesscan be obtained.

(5) Light Guide Plate

The light emitting apparatus may have a light guide plate. As the lightguide plate, for example, any appropriate light guide plate such as alight guide plate having a lens pattern formed on the rear side suchthat light from the lateral direction can be deflected in the thicknessdirection or a light guide plate having a prism shape or the like formedon the rear side and/or the visible side can be used.

(6) Medium Material Layer Between Elements

The light emitting apparatus may have a layer composed of one or moremedium materials (medium material layer between elements) provided onthe light path between the adjacent elements (layers).

Although there is no particular limitation on the one or more mediumscontained in the medium material layer between the elements, examplesthereof include vacuum, air, gas, optical materials, adhesives, opticaladhesives, glass, polymers, solids, liquids, gels, cured materials,optical bonding materials, refractive index matching or refractive indexmismatching materials, refractive index gradient materials, cladding oranti-cladding materials, spacers, silica gel, brightness enhancementmaterials, scattering or diffusion materials, reflective oranti-reflective materials, wavelength selective materials, wavelengthselective anti-reflective materials, color filters, suitable mediumsknown in the art, and the like.

Specific examples of the display apparatus according to the presentinvention include, for example, those equipped with a wavelengthconversion material for EL display apparatuses and liquid crystaldisplay apparatuses.

Specific examples thereof include the followings:

(E1) a backlight that converts blue light into green light or red light,in which a cured product (cured film) composed of the curablecomposition according to the present invention is placed in a glass tubeor the like and sealed, and this is arranged between a blue lightemitting diode, which is a light source, and a light guide plate, alongan end face (side face) of the light guide plate (on-edge typebacklight);

(E2) a backlight in which a laminated film formed by sandwiching andsealing a cured product sheet of the curable composition according tothe present invention between two barrier films is installed on a lightguide plate whereby blue light irradiated from a blue light emittingdiode placed on an end face (side face) of the light guide plate throughthe light guide plate onto the sheet is converted to green light or redlight (surface mounted type backlight);

(E3) a backlight in which the curable composition according to thepresent invention is dispersed in a resin or the like and installed inthe vicinity of a light emitting section of a blue light emitting diodewhereby irradiated blue light is converted into green light or red light(on-chip type backlight);

and

(E4) a backlight in which the curable composition according to thepresent invention is dispersed in a resist and installed on a colorfilter whereby blue light irradiated from a light source is convertedinto green light or red light.

Other specific examples of the light emitting apparatus include alighting in which the curable composition according to the presentinvention is cured and shaped and arranged in the subsequent stage of ablue light emitting diode, which is a light source, whereby blue lightis converted into green light or red light, thereby emitting whitelight.

<Display Apparatus>

As illustrated in FIG. 2 , a display apparatus 3, which is oneembodiment of the present invention, comprises a liquid crystal panel 40and the light emitting apparatus mentioned above, in this order from thevisible side.

The light emitting apparatus comprises a laminated body 1 b and a lightsource 30. The laminated body 1 b further comprises, in addition to thelaminated body 1 a mentioned above, a prism sheet 50 and a light guideplate 60. The display apparatus may further comprise any appropriateadditional members.

(1) Liquid Crystal Panel

The liquid crystal panel described above typically comprises a liquidcrystal cell, a visible side polarizing plate arranged on the visibleside of the liquid crystal cell, and a rear side polarizing platearranged on the rear side of the liquid crystal cell. The visible sidepolarizing plate and the rear side polarizing plate can be arranged suchthat their respective absorption axes are substantially orthogonal orparallel.

(2) Liquid Crystal Cell

The liquid crystal cell has a pair of substrates and a liquid crystallayer as a display medium sandwiched between those substrates. In ageneral configuration, a color filter and a black matrix are provided onone substrate, and on the other substrate, a switching element thatcontrols the electrooptic characteristics of the liquid crystal, ascanning line that provides a gate signal and a signal line thatprovides a source signal to the switching element, a pixel electrode,and a counter electrode are provided. The gap between the substratesdescribed above (cell gap) can be controlled by a spacer or the like. Onthe side of the above substrate in contact with the liquid crystallayer, for example, an oriented film composed of a polyimide can beprovided.

(3) Polarizing Plate

The polarizing plate typically has a polarizer and a protective layerarranged on one side or both sides of the polarizer. The polarizer istypically an absorption type polarizer.

As the polarizer described above, any appropriate polarizer is used.Examples thereof include, for example, those obtained by adsorbing adichroic substance such as iodine or dichroic dye onto a hydrophilicpolymer film such as polyvinyl alcohol based film, partially formalizedpolyvinyl alcohol based film, or ethylene-vinyl acetate copolymer basedpartially saponified film, which is then subjected to uniaxialstretching; polyene based oriented films such as dehydrated products ofpolyvinyl alcohol or dehydrochlorinated products of polyvinyl chloride;and the like. Among the above, polarizers obtained by adsorbing adichroic substance such as iodine onto a polyvinyl alcohol based film,which is then subjected to uniaxial stretching, are particularlypreferable because of their high dichroic ratio of polarized light.

<LED>

As one example of the application of the curable composition accordingto the present invention, mention may be made of, for example, awavelength conversion material for light emitting diodes (LEDs).

The curable composition according to the present invention can be usedas, for example, a material for the light emitting layer of LEDs.

Examples of the LED comprising the curable composition according to thepresent invention include, for example, one having a structure in whicha mixture of the curable composition according to the present inventionand electrically conductive particles such as ZnS is layered in the formof a film, with a n-type transport layer laminated on one side and ap-type transport layer laminated on the other side, and operating undera scheme in which an electric current is applied, the holes of thep-type semiconductor and the electrons of the n-type semiconductorcancel out the electric charges at the joint surface, thereby emittinglight.

<Solar Battery>

The curable composition according to the present invention can beutilized as an electron transport material contained in the active layerof solar batteries.

Although the configuration is not particularly limited, examples of thesolar battery include, for example, a solar battery having a fluorinedoped tin oxide (FTC)) substrate, a titanium oxide compact layer, aporous aluminum oxide layer, an active layer containing the curablecomposition according to the present invention, a hole transport layersuch as2,2′,7,7′-tetrakis(N,N-di-p-methoxyphenylamine)-9,9-spirobifluorene(Spiro-MeOTAD), and a silver (Ag) electrode, in this order.

The titanium oxide compact layer has functions of electron transport,reducing the roughness of FTO, and suppressing the reverse electrontransfer.

The porous aluminum oxide layer has a function of improving the lightabsorption efficiency.

The curable composition according to the present invention, contained inthe active layer, has functions of charge separation and electrontransport.

<Method for Producing Laminated Body>

The method for producing a laminated body may be as follows:

(i) a method including the steps of: coating a substrate with thecurable composition according to the present invention; removing asolvent; and curing the layer of the coated curable composition;

(ii) a method including the steps of: coating a substrate with thecurable composition according to the present invention; and curing thelayer of the coated curable composition; or

(iii) a method including the step of pasting a film formed by curing thecurable composition according to the present invention together with asubstrate.

Although there is no particular limitation on the step of coating asubstrate included in the production methods of (i) and (ii), a publiclyknown coating method such as a gravure coating method, a bar coatingmethod, a printing method, a spray method, a spin coating method, a dipmethod, and a die coat method can be used.

In the step of pasting a film together with a substrate included in theproduction method of (iii), any adhesive can be used.

The adhesive is not particularly limited as long as it does not dissolvethe fluorescent particle (A), and publicly known adhesives can be used.

The method for producing a laminated body may include the step offurther pasting the laminated body obtained in (i) to (iii) togetherwith any film or layer.

Examples of the optional film to be pasted together include, forexample, reflective films and diffusion films.

In the step of pasting the film together, any adhesive can be used.

EXAMPLES

Hereinafter, the present invention will be described furtherspecifically with reference to Examples, but the present invention isnot limited by these examples. In the examples, the percentages andparts representing the content or the amount to be used are on a massbasis, unless otherwise specified.

Production Example 1: Preparation of Fluorescent Particle (A) ContainingPerovskite Compound

After mixing 25 mL of oleylamine and 200 mL of ethanol, 17.12 mL of anaqueous hydrobromic acid solution (48% by mass) was added with icecooling and stirring, and then the precipitation was obtained by dryingunder reduced pressure. The precipitation was washed with diethyl etherand was then dried under reduced pressure, thereby obtainingoleylammonium bromide. Into 21 g of the obtained oleylammonium bromide,200 mL of toluene was mixed, thereby preparing a solution containingoleylammonium bromide.

1.52 g of lead acetate trihydrate, 1.56 g of formamidine acetate, 160 mLof 1-octadecene as a solvent, and 40 mL of oleic acid were mixed. Afterstirring and heating the mixture to 130° C. with nitrogen flowing, 53.4mL of the solution containing oleylammonium bromide mentioned above wasadded thereto. After the addition, the temperature of the solution waslowered to room temperature to obtain a dispersion liquid 1 containing afluorescent particle 1.

A solution obtained by mixing 100 mL of toluene and 50 mL ofacetonitrile into 200 mL of the dispersion liquid 1 described above wassubjected to solid-liquid separation by filtration. Thereafter, thesolids on the filtration were washed with a mixed solution of 100 mL oftoluene and 50 mL of acetonitrile twice and then filtered. As a resultof this, the fluorescent particle 1 was obtained.

The obtained fluorescent particle 1 was dispersed with toluene to obtaina dispersion liquid 2.

When the dispersion liquid 2 was subjected to an XRD measurement, theXRD spectrum had a peak derived from (hkl)=(001) at the position of2θ=14.75°. From the measurement results, it was confirmed that therecovered fluorescent particle 1 is a compound having a threedimensional perovskite type crystal structure.

For the XRD measurement of the dispersion liquid 2, XRD, CuKα radiation,X'pert PRO MPD, manufactured by Spectris Co., Ltd. was used.

After dissolving the perovskite compound by adding N,N-dimethylformamideto a part of the dispersion liquid 2 described above, the fluorescentparticle (A) composed of the perovskite compound was measured usingICP-MS (manufactured by PerkinElmer Co., Ltd., ELAN DRC II) and ionchromatograph (manufactured by Thermo Fisher Scientific K.K., Integrion)and found out to be 1500 ppm (μg/g).

Into 200 mL of the dispersion liquid 2 described above, toluene wasmixed such that the concentration of the fluorescent particle 1 became0.23% by mass. To this, 1.9 parts by mass of organopolysilazane (1500Slow Cure, Durazane, manufactured by Merck Performance Materials Ltd.)was added per 1 part by mass of the fluorescent particle 1 in thedispersion liquid 2. Subsequently, a modification treatment with watervapor was performed for 4 hours to obtain a dispersion liquid 3containing the fluorescent particle (A).

The modification treatment conditions at that time were set as follows:the flow rate of water vapor was 0.2 L/min (supplied together with N₂gas, saturated water vapor volume at 30° C.) and the heating temperaturewas 80° C.

Examples 1 to 9 and Comparative Examples 1 and 2: Preparation of CurableComposition and Fabrication of Cured Film

(1) Preparation of Curable Composition

Curable compositions were prepared by mixing the dispersion liquid 3containing the fluorescent particle (A) composed of the perovskitecompound obtained in Production Example 1 and other compoundingcomponents shown in Table 1, and then removing toluene with anevaporator (for Comparative Examples 1 and 2, no antioxidant was added).The compounding ratio of each compounding component was adjusted suchthat the amount to be compounded for each compounding component is theamount shown in Table 1 when the content of the fluorescent particle (A)in the curable composition is 1.0 parts by mass (for Example 9 andComparative Example 2, 0.9 parts by mass). In Table 1, the unit of theamount to be compounded for each compounding component is in parts bymass.

The details of each compounding component shown in Table 1 are asfollows:

[a] EH-A: 2-ethylhexyl acrylate;

[b] TMPT-A: trimethylolpropane triacrylate;

[c] Photopolymerization initiator (C): “omnirad 819”(phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide) manufactured by IGMResins B.V.;

[d] Amine based 1: an amine based antioxidant (manufactured by BASF SE,trade name “Tinuvin 770”);

[e] Amine based 2: an amine based antioxidant (manufactured by ClariantAG, trade name “Hostavin PR31”);

[f] Phenol based 1: a phenol based antioxidant (manufactured by BASF SE,trade name “Irganox 1076”);

[g] Phenol based 2: a phenol based antioxidant (manufactured by ADEKACORPORATION, trade name “ADEKASTAB AO-40”);

[h] Phenol based 3: a phenol based antioxidant (manufactured by ADEKACORPORATION, trade name “ADEKASTAB AO-80”);

[i] Phenol based 4: a phosphorus-phenol based antioxidant (manufacturedby Sumitomo Chemical Co., Ltd., trade name “SUMILIZER GP”);

[j] Sulfur based: a sulfur based antioxidant (manufactured by SumitomoChemical Co., Ltd., trade name “SUMILIZER TPM”);

[k] Phosphorus based: a phosphorus based antioxidant (manufactured byADEKA CORPORATION, trade name “ADEKASTAB 1178”); and

[l] Quantum dot: an InP/ZnS core-shell type quantum dot (quantum dotthat can be synthesized by a commonly known method (Journal of AmericanChemical Society. 2007, 129, 15432-15433) disclosed in Japanese PatentLaid-Open No. 2016-65178).

(2) Fabrication of Cured Film

The curable composition was applied to a first polyethyleneterephthalate (PET) film, using a bar coater. A second PET film wasplaced on top of the applied layer, and after sandwiching the appliedlayer with the two PET films, the applied layer was cured by irradiatingthe applied layer with ultraviolet light (UVA) from a high pressuremercury lamp in the air. The thickness of the cured film thus obtainedwas 30 μm. The accumulated amount of light for the ultraviolet lightirradiation was set to 300 mJ/cm².

[Evaluation Test]

[1] Heat Resistance Test

As for the laminated body composed of the first PET film/the cured filmof the curable composition/the second PET film obtained in “(2)Fabrication of cured film” described above, the quantum yield (%) wasmeasured at an excitation light of 450 nm, at room temperature, andunder the atmosphere, using an absolute PL quantum yield spectrometer(manufactured by Hamamatsu Photonics K.K., C9920-02). This quantum yieldis defined as “QY (after film formation)” (%).

Subsequently, as for the laminated body composed of the first PETfilm/the cured film of the curable composition/the second PET film, aheat resistant test was performed by retaining the laminated body in theair at a temperature of 150° C. for 90 minutes, and the quantum yield(%) was measured for the laminated body after the heat resistance testin the same manner as described above. This quantum yield is defined as“QY (after heat resistance test)” (%).

The QY maintenance rate A was calculated based on the followingexpression.QY maintenance rate A (%)=100×QY (after heat resistance test)/QY (afterfilm formation)

When the QY maintenance rate A is higher, a decrease in the quantumyield of the cured film due to heat is smaller. The QY maintenance ratesA in Examples and Comparative Examples are shown in Table 1.

[2] Stability Over Time Test of Curable Compositions

For a sample obtained by applying the curable composition before curingonto glass, the quantum yield (%) was measured at an excitation light of450 nm, at room temperature, and under the atmosphere, using an absolutePL quantum yield spectrometer (manufactured by Hamamatsu Photonics K.K.,C9920-02). This quantum yield is defined as “QY (initial)” (%).

Subsequently, a stability over time test was performed in which thecurable composition before curing was retained in a sample bottle in theair and at a temperature of 23° C. for 12 days, and for the sample afterthe stability over time test, the quantum yield (B) was measured in thesame manner as described above. This quantum yield is defined as “QY(after stability over time test)” (%).

The QY maintenance rate B was calculated based on the followingexpression.QY maintenance rate B (%)=100×QY (after stability over time test)/QY(initial)

When the QY maintenance rate B is higher, the stability of the curablecomposition over time (storage stability) is higher. The QY maintenancerates B in Examples and Comparative Examples are shown in Table 1.

TABLE 1 Exam- Exam- Exam- Exam- Exam- Exam- Exam- Exam- ComparativeExam- Comparative ple 1 ple 2 ple 3 ple 4 ple 5 ple 6 ple 7 ple 8Example 1 ple 9 Example 2 Fluorescent particle (A) 1.0 1.0 1.0 1.0 1.01.0 1.0 1.0 1.0 0.9 0.9 Photo- EH-A 83.0 83.0 83.0 83.0 83.0 83.0 83.083.0 83.4 83.0 83.4 polymerizable TMPT-A 15.0 15.0 15.0 15.0 15.0 15.015.0 15.0 15.1 15.0 15.1 compound (B) Photopolymerization initiator (C)0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Antioxidant Amine based 10.5 (D) Amine based 2 0.5 Phenol based 1 0.5 Phenol based 2 0.5 Phenolbased 3 0.5 Phenol based 4 0.5 0.5 Sulfur based 0.5 Phosphorus 0.5 basedQuantum dot (E) 0.1 0.1 Evaluation QY 76 78 82 84 85 87 86 85 65 36 20results maintenance rate A (%) QY 85 50 96 97 97 95 86 73 67 60 39maintenance rate B (%)

REFERENCE SIGNS LIST

-   -   1 a, 1 b Laminated body    -   10 Film    -   20, 21 Substrate    -   3 Display apparatus    -   30 Light source    -   40 Liquid crystal panel    -   50 Prism sheet    -   60 Light guide plate    -   70 Light reflective member

The invention claimed is:
 1. A curable composition comprising afluorescent particle (A) containing a perovskite compound, aphotopolymerizable compound (B), a photopolymerization initiator (C),and an antioxidant (D), wherein the content of the antioxidant (D) is0.1% by mass or more and 20% by mass or less in 100% by mass of thesolid content of the curable composition.
 2. The curable compositionaccording to claim 1, wherein the antioxidant (D) comprises at least onekind selected from the group consisting of amine based antioxidants,sulfur based antioxidants, phenol based antioxidants, and phosphorusbased antioxidants.
 3. The curable composition according to claim 1,further comprising a quantum dot (E).
 4. The curable compositionaccording to claim 1, wherein the antioxidant (D) comprises a phenolbased antioxidant.
 5. A film formed by curing the curable compositionaccording to claim
 1. 6. A laminated body comprising the film accordingto claim 5 and a layer other than the film.
 7. A display apparatuscomprising the laminated body according to claim 6.